Gastrointestinal | Salivation: Parotid, Submandibular, & Sublingual Glands

470.82k views6887 WordsCopy TextShare
Ninja Nerd
Official Ninja Nerd Website: https://ninjanerd.org Ninja Nerds! In this lecture Professor Zach Murp...
Video Transcript:
iein innards in this video we are going to talk about salivation soul I've asked so many important functions so many alright when I talk about some of the few and we'll talk about them in more detail but saliva is actually really important for being able to hydrate the oral cavity rays what hydrates the oral cavity it helps to lubricate the food that we actually ingest and chew up and swallow to make it more of a nice compact mass called a bolus you know what else is really cool about the saliva and has special enzymes in
it what kind of enzymes digestive enzymes you know there's two different types of enzymes one is actually called salivary amylase and the other one is called lingual lipase salivary amylase is really good for being able to digest and chemically break down polysaccharides lingual lipase is actually to a minor effect pretty good at being able to break down lipids so we have helping to hydrate the oral cavity helping to actually lubricates the food substances and being able to have a rolling chemical digestion but there's another one you know it actually is good for oral hygiene you
know there's a bunch of different types of enzymes and proteins that are important to be able to fight off different bacteria and viruses and fungi and to prevent dental caries or in other word cavities so there's a lot of cool things that are gonna come from the saliva so let's go ahead and dig right in so the first thing I want to talk about is where does saliva come from from salivary glands but we have to understand there's actually two types of salivary glands okay what are those two types and the two types of salivary
glands is you're gonna have your extrinsic salivary glands and you'll have your intrinsic salivary glands the extrinsic means that they're outside of the oral cavity well they're outside of the oral cavity what are some of these these are going to be your parotid gland maybe parotid glands they're actually paired they're on specifically anterior to the ears and they're in between the masseter muscle and the skin right so that's your pirata glance another one is actually going to be found on the inner medial surface of the mandibular body they say it's actually sits on what's called
the digastric triangle but that is going to be called the sub mandibular glands and then you have one more and this is actually kind of sitting underneath the tongue and this next one is called the sub lingual salivary glands now what's important here is that if these are extrinsic meaning they're located outside of the oral cavity how in the heck does the saliva get into the oral cavity well these things have what's called ducts and these ducts can travel from the glands into the oral cavity we'll talk about some of those ducts and a little
now the next thing is we have to talk about the intrinsic salivary glands the intrinsic salivary glands there's actually a bunch of them there's the buccal glands there's the lab EO glands which is for the lips there's the Palatine glands there's a whole bunch right these are some of the a couple of them what is this the big difference between the extrinsic and intrinsic well one is these are located in the oral cavity but another really important thing that I want you guys to get with intrinsic salivary glands is they are secreting saliva at a
constant rate but they only account the intrinsic salivary glands only account for 10% of the salivary volume whereas the extrinsic salivary glands they are secreted based upon a stimulus and we'll talk about the two stimuli like Meccano receptors can pick up certain types of chewing reflexes or certain types of things that we have within the oral cavity and chemo receptors that are highly stimulated by acidic substances okay so we got the big big thing down to types of glands they're the ones that make the saliva extrinsic intrinsic next thing I want to talk about here
is those ducks what are those ducks so let's pretend we go in order here as we did down here parotid submandibular and sublingual so again what is this one right here this one right here is going to be the parotid gland this one right here is going to be this sub mandibular salivary gland and this one is going to be this sub lingual salivary clamp these are your extrinsic ones now we said they're located outside of the oral cavity we said the parotid is right here anterior to the ear in between the masseter muscle and
skin but it has a little duct here and this duct actually travels and pierces through a couple muscles and what it does is it empties into the oral cavity around the second upper or maxillary molar you can say two ways you can say it empties in between around into the oral cavity through what around the second maxillary molar or upper molar so you can say second maxillary or second upper molar now the question is what is this duct that actually travels from the gland to the oral cavity this right here is called the parotid duct
pretty simple right the parotid duct another name for this is see if you really want to remember is the Stenson's duct okay but again this doctor is going to be traveling and taking the saliva to the oral cavity now the next one the next one is the submandibular salivary gland and this one is gonna have a duct that travels all the way to the oral cavity but specifically you know the tongue it has like this little thing right here that anchors the tongue down it's called the lingual frenulum and there's little holes right here around
the lingual frenulum and this is where the submandibular duct actually opens right at the base of the tongue called the lingual frenulum so what could the structure here be called it's called the lingual frenulum now he has a duck that actually connects to the lingual frenulum that duck is called the submandibular duct another name for it is Wharton's duct okay so this is gonna actually this duct right here we're gonna use Wharton's but it's gonna be called Wharton's duct or the submandibular duct warden's doc or the submandibular duct now last one here is the sublingual
salivary gland the sublingual salivary gland will where you find it you'll find it underneath the tongue so you'll find it at the base of the tongue now this one's really interesting this right here this doc it's actually a lot of them there's actually about 10 to 20 of these ducts that empty up into the the floor of the oral cavity so there's a lot of these ducts they actually call the ducts of Riven as' don't need to really know that but these guys empty into the oral cavity the floor of the oral cavity so we
know how the extrinsic sout we know what the extrinsic salivary glands are we know the ducts that take them to the oral cavity and we know exactly whereabouts they actually put their saliva into the oral cavity the next thing I want to talk about is very briefly about the histology of the actual parotid salivary gland the submandibular in the sublingual we're not gonna go into crazy detail but there when you look at this I guys under a microscope they actually have some of them have different types of cells that make them up there's two types
serous cells there's two types here for the extrinsic serous cells which are the ones that are making more of the watery secretion very enzyme rich types of secretions the other one is your mucous cells and the mucous cells are going to be the ones that are making more of the electrolyte water laws dis electrolyte and water decreasing amount of substances and more of a glycoprotein mucin rich substance it's more stringy more viscous it's - it's a good to be able to lubricate the foodstuffs and to be able to hydrate the oral cavity and dissolve some
of the food substances that we're eating so that they can be tasted by the tastebuds right so two types of cells now the parotid salivary gland primarily consists of serous cells okay so the parotid salivary gland is primarily gonna be consisting of here we'll put like this serous cells okay the submandibular is going to be mixed it's going to be mixed so this one is going to be mixed with this serous and the mucous cells and the last one is the sublingual salivary gland and it primarily contains mucous cells with a very very tiny amount
they do say it's a little bit mixed but for simplicity sake we're gonna say mucus cells but they do be aware they do contain a small amount of serous cells okay your intrinsic salivary glands they're primarily mucous cells okay so these ones your intrinsic are primarily mucous cells okay now that we understand that now let's go ahead and talk to what are we talking we talked about the extrinsic salivary glands intrinsic where are they empty extrinsic wise right we talked about what type of histological cells they're made up of now we need to talk about
the innervation of these glands alright so now I want to talk about the innervation and then we'll talk about some reflexes and then we'll zoom in onto the cells and see how this alive is being made okay so first things first if you guys haven't already watched the video on the glossopharyngeal nerve and the facial nerve I would urge you guys to do cuz we're gonna we go over that in more detail here we are gonna breeze right through it okay so first things first let's start up here in the actual brainstem you know in
the brainstem you have a special nucleus right here a nucleus within the brainstem specifically around the pons this guy is called the superior Salvatori nucleus okay so you have a superior Salvatori nucleus guess what you have just inferior to that just a little bit below it the inferior Salvatori nucleus let's do that one in green okay so right here you're gonna have the inferior salivatory nucleus now the superior Salvatori nucleus is gonna be part of the facial nerve if you guys remember the facial nerve it's gonna come out here right it's gonna come out right
around that kind of like that pons medulla Junction there then what it does is it goes through a hole in the skull if you guys remember it's right around here you know there's what's called the internal acoustic meatus the internal acoustic meatus this guy goes right through this hole called the internal acoustic meatus or along with the vestibular cochlear nerve when it goes out through the internal acoustic meatus it comes out here right it goes to a specific area you know um you have your middle ear cavity in the middle ear cavity you have the
structure here and it's a little bony canal you know you have this little thing right here this little bony canal right here the facial nerve is going to traverse through that little bony canal which is in the medial and posterior wall of the middle ear cavity then what it does is it actually comes out of that bony canal and then what it does is it moves anteriorly it moves anteriorly and it comes out through this tiny little hole this little anterior canaliculus and goes out from here and that crazy so now what do we have
here we're gonna have the superior celebratory nucleus the fibers are going to be coming out here through the internal acoustic meatus then after that it's going to come through the bony canal within the middle ear cavity come out this actual bony canal and then move anteriorly you know what else it moves with we're not gonna talk about a super depth but there's some taste fibers that actually run with that also you know the taste fibers you're sp fibers and these gve fibers which are these Salvatori fibers together they make up what's called the chorda tympani
okay now reason I'm telling you this is because what happens is the chorda tympani actually combines with some of the trigeminal nerve fibers we're not going to talk about that right now but it actually combines with a specific nerve and that is going to be called the lingual nerve so you have what's called the lingual nerve which is a branch of the trigeminal nerve and when it combines with the lingual nerve it goes to a specific area it goes to the tongue well on its way it hops off it gets off of the actual lingual
nerve and stops at a ganglia okay it stops at a ganglia what do you think is ganglia is called this ganglia is called the sub and let's actually put it over here this is called the sub mandibular ganglion so it's called the sub mandibular gangly on from here these are your pre ganglionic parasympathetic fibers from this point you're gonna have your parasympathetic postganglionic fibers and that is gonna go to the submandibular salivary gland and the sublingual salivary gland and innervate these guys and cause them to see create the different components for the saliva alright so
now we talked about how the submandibular and the sublingual salivary gland are supplied by the seventh cranial nerve coming from the superior salable to our nucleus so again this is cranial nerve seven facial nerve right now that's gonna give us the supply to the sub n deeper than the sublingual but what about the parotid that's gonna come from the glossopharyngeal nerve or cranial nerve nine and that was going to be from this nucleus let's use a different color let's make it a little bit darker actually it's a little better here for the camera right so
let's do inferior salivatory nucleus and again what nerve is this going to be for this is for cranial nerve nine which is the glossopharyngeal if you guys know a little bit about the anatomy again you know there's a hole in the skull which is called the jugular foramen and this nerve traverses right through that right so here's gonna be the jug of the frame and here's your glossopharyngeal nerve and it's gonna pass right through that then what it's gonna do is it's gonna enter into the middle ear cavity now there's a hole on the floor
of the middle ear cavity like imagine there's like a little hole right here I'll draw it there's a little hole right there alright this is gonna come up into the actual middle ear cavity through that hole okay it's called the tympanic canaliculus then from here it's gonna come onto this promontory on the medial wall of the tympanic cavity the middle ear cavity and it has some branches that it gives off here but either way from here it's gonna come as a special type of nerve they actually call this nerve the lesser petrosal nerve now what
happens is the lesser petrosal nerve is actually going to go through a hole in the skull which is called the hiatus of the lesser petrosal nerve then from there it actually will enter it'll go into the middle cranial fossa and it'll come back out he'll come back out of the middle cranial fossa and when it comes back out of the middle cranial fossa it'll actually come out through a special type of hole and this one is called the foramen oh wow foramen ovale you know what other nerve runs through the foramen ovale the trigeminal nerve
v3 the mandibular division of the actual trigeminal nerve now from here this lesser petrosal nerve is going to come up through the hiatus of the lesser petrosal nerve into the middle cranial fossa back out through the foramen ovale and then it goes downwards then from here it's gonna come to a special ganglia a group of cell bodies within the peripheral nervous system what is that ganglia call this ganglia is called the otic ganglion okay it's called the otic ganglion from here it's gonna sign apps on the postganglionic cell bodies for the parasympathetic motor fibers and
from here these postganglionic sympathetic motor fibers will then go to the parotid gland and stimulate the product land to undergo certain celebratory mechanisms so now we know the actual efferent supply to these glands the next thing I want us to realize is okay how do these nerves know when to fire and send these impulses well that's a good question inside of the oral cavity there's special types of receptors special receptors and you know within the oral cavity you have these special here let's let's say here some receptors right here here's some receptors and they're all
over the place right you have some receptors that can be present on the tongue you have some receptors that are present within the cheeks you have receptors that can be present around the tonsillar fossa and tonsillar pillars and the pilato gloss arch and plot of Fringe charge all that area there and what happens is let's say that there is a stimulus to this type of receptors what type of receptors we say chemo receptors or we say Meccano receptors if there is some type of chemical or mechanical stimulation again a chemical stimulation what type of things
acidic stimuli so foods that are highly acidic that can actually increase the salivate it's a salivation mechanism also chewing certain types of substances that we chew on that can also activate these mechanoreceptors which can enhance the salivation mechanism so this is common from chewing these chemo receptors and mechanoreceptors they'll pick up these informations right they'll pick up the information and they'll send this information back to the actual brain stem so let's pretend that we take this guy here and we take this information and it comes in and stimulates these two areas right here what's going
to happen from here it's going to activate these two and motor fibers to send their information down to these glands and undergo the salivation mechanism start salivating another thing that can happen is not even anything in the mouth you never see something he just like mmm and the study starts salivating from it what does that do the sight of food so sometimes the sight of food right the sight of food can also stimulate salvation the thought of food can stimulate salvation maybe even the smell of food can simulate salvation so what other things can stimulate
the salivation the sight of food can stimulate salvation the thought of food can stimulate salvation right so thought the sight what else the smell even the smell of food have ways that they can stimulate the salivation mechanisms which is so darn cool this is related when we'll talk about it later to the cephalic phase of gastric secretions because not only do you salivate when you have the sight or thought or taste or smell of food but also you start producing gastrics substances specifically hydrochloric acid and pepsin we'll talk about that whenever we get to those
videos okay so now we've covered what stimulates the release from these glands we talked about what fibers can stimulate these glands to release saliva we talked about the histology we talked about the difference between these glands and the glands that are inside of the oral cavity and we talked about how these glands are connected to the oral cavity one last thing I have to talk about then we'll get into this mechanism over here is these are parasympathetic fibers right so these two here cranial nerve seven and cranial nerve nine these are for your parasympathetic nervous
system and these are designed to be able to increase the volume of saliva okay so his whole goal is to increase the volume of saliva the secretions right specifically you want to be more watery more electrolyte rich so this is the kind that what you want this to be really water rich and electrolyte rich and we'll talk about how it does that when you zoom out on the glans but then you have to have the opposing system the sympathetic nervous system you know if you guys remember we have you know the different parts of the
spinal cord which is again extending from what levels we said from t1 all the way down to l2 we'll just have it going to this point here ok and specifically like t1 all the way to t3 maybe even t4 can go up to the head and neck region you remember this we said that these guys can go to some ganglia up here like the superior cervical ganglia so what is this gangly right they're called we're going to denote it s C G superior cervical ganglion then from here what can these fibers do the superior cervical
ganglion from here it can actually give off these fibers and they course around if you guys remember we showed that so many times in many videos pretend here we have the carotid artery here right and then surrounding that carotid artery wrapping around it pretend here is the superior cervical ganglion these fibers wrap around the carotid artery there called the carotid plexus and then from here they can come off and go to these different types of glands so what I want you to remember here is pretend there's actually the carotid artery running through here we'll do
it like this here's gonna be the carotid artery ok there's your carotid artery what does these fibers gonna do they're gonna come over here they're gonna wrap around this and then from here they can go out to different structures from here they can either you know they can actually go into this little pterygoid canal and then from here they can go into the tear go Palantine fossa and then from here they can go out to these different types of glands so from here they can come out and supply these glands they can supply the parotid
can supply the submandibular and you can even supply the sublingual ok this nerve that really goes and does this they actually call this one the deep petrosal nerve if you guys really wanted to know that they actually call this one the deep petrosal nerve but again big big thing i want you to get out as this the whole point to take away from this is the sympathetic nervous system is going to have an effect on these salivary glands what is its goal and again usually from t1 to t4 the sympathetic nervous system is focusing on
saliva that is protein rich saliva that is protein rich that is the goal and this saliva is going to be a lot thicker so we're also gonna have saliva that's gonna be really protein rich but because of that it's gonna be a thicker more viscous saliva okay we'll talk about why okay so now we have understand that let's go ahead take one of these glands and zoom in on it okay so I'm zooming in on one of these glands here you have a whole bunch of see how this is like more of the sac like
a region of this gland they call this where the a' sinesses right this is the ascendance and you have your sin ourselves and this is a duck so these is that you know that there's different types of duck striated inter lobular intercalated ducts excreta tori ducts we're just gonna say this is a duck and these are your ductal cells things happen and the ascendance and in the ducts that we needed to get a little bit of a talked about so now you know you're gonna have blood vessels coming to this area here let's pretend it's
real quick here's a blood vessel right doesn't have to be anything special just a quick blood vessel here cuz I just want you guys to get an idea that blood flow is coming to these glands and the blood flow actually can help to determine the amount of saliva we make to a small degree now where some of those chemicals that we talked about that we were releasing or if you remember the parasympathetic nervous system is primarily going to be releasing acetylcholine right that's its job to release acetylcholine whereas the sympathetic nervous system was releasing Noro
epinephrine okay before we talk about what these guys are doing on the cells let's see how these glands start actually making saliva first and let's see how these can help to impact that so you know on this is the basolateral membrane right here and this is your apical membrane we have different types of transporters throughout all of these let's just say first one we have is right here okay so we zoom in on this one so right here I'm gonna have a special type of protein molecule and what this protein molecule is doing is it's
taking and pumping into the cell two potassium ions and pumping out three sodium ions okay that's the first thing let's say we have another transporter and that transporters right here here's another transporter on the basolateral membrane let's say that this bad boy is pumping in sodium is pumping in potassium and it's pumping in two chloride ions let's have another transporter on the basolateral membrane let's do this one in blue this guy let's say that this one is pumping bicarbonate you know you know you actually have a specific molecules like bicarbonate let's say that here we're
gonna have some bicarbonate and you can also have cola ride - what we can do here is we can take this bicarbonate and we can actually pump this bicarbonate out here into the blood and we can take chloride ions and pump them in okay now let's talk about these there's a lot of ions we're gonna see out here primarily what we are gonna see out here is you're gonna see sodium you are going to see potassium you're gonna see chloride you're gonna see bicarbonate you might even see some calcium and some phosphate we're not gonna
talk about those in great detail and you're going to see water now I want us to focus on how do we get those substances in well water is the easiest one you know on our these guys over here they have these de special types of proteins special types of proteins called aquaporins you know they're the special one here is actually called aquaporin v you know aquaporin v you know what it actually it allows for it allows for the water to leak out through the apical membrane out into this area so that's going to facilitate the
water movement out here you know where else the water can move it can move between the cells so you know there's actually the ability for the water to move between the cells - what does that call whenever the water is being transported between the cells it's called para cellular transport there's another thing too you know on the other part of the membrane the basolateral membrane let's say the water doesn't want to move between the cells there's another transporter which can take the water into the cell first and then from there guess where that can go
it can go out through the aquaporin v this right here is called aquaporin 3 so just a little bit on there is now we know that the water can get into this area through aquaporin 3's aquaporin 5s or it can go out through peri cellular transport guess what sodium it goes through Paris cellular transport sodium's main mechanism in which it actually gets drug in here is going to be via para cellular transport okay so now we know how we got sodium in here we know how we got water in here how do we get the
potassium in here okay remember we had over here these uh Petoskey the sodium potassium ATPase is was pumping the sodium out bringing the potassium in well guess what that potassium now we have channels right here we have some protein transporters right here and what these can do is they can take the potassium ions and push the potassium ions out but in exchange we have to pump a proton in so that's one way we can get the potassium ions out all right that's one way another way we can do is remember over here we had these
sodium potassium to chloride Co transporters that can get the actual potassium in here and then from here the potassium can actually either leak out through leakage channels right or it could go again through those potassium hydrogen pumps okay what about the chloride about the chloride well again look it over here remember we had these transporters right here over these ones again the sodium potassium to chloride Co transporters and they were pumping for approximately two chloride ions in you know there's special types of channels located on the apical membrane for the chloride they're called CF t
are types of proteins this is like a cystic fibrosis transmembrane receptor protein right here this guy is going to allow for these chloride ions to leak out here so they can get brought in through these sodium potassium to chloride code transporters and then go out through these CFTR proteins alright that's another way we can get a chloride out so now we have the chloride we have the sodium we have the potassium out here we have the water what about that bicarb if you guys don't know this mechanism by now by watching our videos shame on
you watch this okay so again what's a byproduct of our cells co2 what is co2 combined with inside of ourselves water when these two combine in the presence of an enzyme called carbonic anhydrase i'm going to donate at sea a it becomes h2 co3 which is carbonic acid then carbonic acid is broken down into protons and bicarbonate guess what I can do with that bicarbonate I can excrete that bicarbonate out so I can excrete that bicarbonate out here and sometimes what happens is as a result I bring some chloride molecules in here to to be
able to maintain the electoral selectivity there right but now you've seen here how bicarbonates gotten out here you see how chloride now here potassium and sodium and water we know this mechanism now okay so we have covered all of these bad boys we know now how these substances get in but I want to tell you one more thing sodium and chloride when they're pulled into this area so let me make one important point sodium and chloride the amount that's pulled into this actual aseneth is equal to the amount of water that's being pulled into this
area so because of that this fluid that's sitting in this area this is called this is actually called the primary secretion this fluid is isotonic to the blood plasma so the actual tonicity the osmolality of your blood plasma is going to be equal to the actual solute concentration inside of this aseneth that is important but guess what things got to change so then from here you've made these the substances they're going to go into the ducts well when we come out here when they come out the sodium isn't going to be that high the chloride
ions aren't gonna be that high but guess what there's gonna be a decent amount of potassium there's gonna be a decent amount of bicarbonate ions how does that happen well once you get over here guess what remember the sodium the sodium molecule here we can bring the sodium in and then what we can do is if we bring the sodium molecule in what we're gonna do is we're gonna pump a proton out I guess what that protons kind of threw so we got the proton out there sodium is gonna come in that's what we can
get the sodium in so that's going to decrease the concentration of the sodium what else when we said the chloride concentration such a decrease so there's also going to be channels over here let's say right here where I can bring the chloride molecules in and sometimes that might be related to the bicarbonate excretion so now I've pulled in chloride I've pulled in sodium so my sodium concentration and chloride concentration are going to decrease right that iron the sodium concentration and the chloride concentration are going to decrease so they're not going to be equal to the
amount of water that's in this area now it's not equal it's less than the amount of water this is the secondary secretion or we call it the modification step this is like the modification step now if the solute concentration is less than the actual water concentration what do we call that we call that hypotonic so this is going to be hypo tonic in relationship to the blood plasma meaning there's more water and less solutes so again what would you see out here also you'll see a decent amount of water okay so now we know how
these things are working naturally now what we have to do is we have to add on to this we have to say okay how does the sympathetic nervous system and how does the parasympathetic nervous system alter this because these aren't the only things that are present inside of the saliva other things that we can find this out of the saliva is going to be dependent upon these different types of molecules so let's say here we have acetylcholine let's actually do a different color let's do this one in this brown here here's a co choline acetylcholine
is going to act on special receptors on the membrane you know there's what's called muscarinic receptors particularly m3 muscarinic type 3 receptors Aseel choline will bind on to this muscarinic receptor and stimulated you know what type of proteins in here g q GQ is normally bonded GDP but it gets rid of it instead it binds gtp from here it then goes and stimulates an enzyme right here what is this enzyme this enzyme is called phospholipase C phospholipase C is then going to break down pip2 phosphatidyl in a SCYTL diphosphate into two components one is called
d AG and the other one is called i p3 i p3 is then going to stimulate increase in calcium levels inside of the cell guess what this is gonna do this calcium as its levels increase they're gonna you know these guys are going to activate dag activates protein kinase II and this activates cam kinase is what these guys these kinase azar gonna go and do is they're gonna phosphorylate certain types of channels and what that's gonna do is it is going to increase the secretion of substances like water like sodium like chloride like potassium and
bicarb and so now what are we going to see out here we're gonna see an increase in the water secretion and electrolyte secretion so now the volume of substances that are being released is increasing due to that mechanism there now what's the other one let's do this one and blow maybe blue you're gonna have that norepinephrine remember the norepinephrine it's gonna by not two special receptors they say that this one's primarily that of like a beta receptor they're not quite sure if it's a beta 1 or beta 2 I think it might be a beta-2
adrenergic receptor but either way there's no epinephrine combined on here and we're gonna say that for most part beta-2 adrenergic receptors when it does that the norepinephrine it activates AG stimulatory protein which is normally bonded gdp gets rid of it binds gtp becomes activated goes and stimulates an effector enzyme located in the actual cell membrane this is called adenylyl cyclase adenylyl cyclase converts ATP into cyclic a and P and then cyclic a and B activates protein kinase a and guess what protein kinase a does you know there's granules you know there's different types of secretory
granules that are present with inside of these cells and inside of these granules you have a lot of proteins and enzymes and different things like that well these protein kinase a is gonna go and stimmy the exocytosis of these granules and then from here I want to look exocytosis I'm gonna release out a whole bunch of different enzymes and proteins what are some of these molecules the big one that it's going to release out is mucin it's gonna release a lot of mucin another thing it's gonna release a lot of is salivary amylase so what
is the big big thing here the sympathetic nervous system is going to try to increase the protein content inside of the saliva which is specifically mutant mutant is a glycoprotein that actually causes the saliva to be a little bit thicker so you're gonna see a thick and viscous saliva another thing it does is remember there's receptors let's pretend here's a receptor on the tunica media norepinephrine combined on to the blood vessels that are supplying these glands if you do that what's it gonna do here it's gonna vaso constrict the blood vessel by vasoconstricting the blood
vessel what are you gonna do the blood flow it's gonna decrease the blood flow if you decrease the blood flow you know all these ions that we've been pushing them in from it's been coming from the blood so if you decrease the blood flow you decrease the amount of ions that are gonna be secreted so you decrease the electrolyte and water secretions that's another reason why that's important okay now there's other things that I wanted to mention real quickly here for the saliva what is the big overall functions of saliva big overall functions oral hygiene
next thing is also going to be what we said that it's going to be antimicrobial so it has antimicrobial activity and we'll talk about how that is very briefly in a second the next thing we said is it helps with chemical digestion and it helps to be able to hydrate the oral cavity and food stuffs and on top of that it helps to increase the taste of substances it helps to increase the taste of food because when that that saliva helps to be able to lubricate it and allow for it to get absorbed into the
taste buds and it actually decreases the incidence of cavities or dental caries okay now really quickly we already have an idea the antimicrobial substances you know there's special types of antibodies that are released into this area you know there's what's called ig8 antibodies that's one really important thing that you can find saliva other important things is you'll find what's called sis statins and his statins these are really good at being able to kill different types of bacteria and fungi and viruses there's even other molecules that you can find out here like lysozymes lyso zaimes these
are good at being able to break down different types of bacterial cell walls instruction even help to digest food substances but one more one that i got our mention here there's something that helps to be able to maintain the mineralization of our teeth and our enamel it's really really important they're called prolene rich proteins and these are really important for being able to help to maintain the enamel maintain the mineralization of the teeth so that pretty much is gonna cover most of the saliva mechanisms all right ninja nerds if you guys stuck in throughout this
video thank you guys so much I hope you guys learned something I hope you guys got something from this and I hope it made sense I really do if you guys did liked this video please hit that like button comment down in the comment section and please subscribe guys please also if you guys get a chance please check out our Facebook or Instagram even our patreon account we would truly appreciate it all right ninja nerds as always until next time [Music] you [Music]
Copyright © 2024. Made with ♥ in London by YTScribe.com