excitation contraction coupling.wmv

Description of excitation contraction coupling... how a neuronal signal causes a muscle fiber to contract. Recorded at Glen Oaks Community College, Centreville, Michigan by Dr Ren Allen Hartung.

[@daviddorfer4612]

I have a great professor, but having this available to see repeatedly is extremely helpful. Thank you!

[@jhonnyfens4586]

HAHA I can study for like one month, with my books or just simply watch your movie's two times! Just simply a perfect explanation again!! Thank you very much!!

[@1tippytop]

I have been studying and trying to understand excitation contraction coupling for the past 2 weeks..I had ALL the correct pieces to this puzzle, but I just couln't see the whole the picture. It was driving me crazy..especially since I knew this is going to be on the final...I watched your video the first time and BAM!!!...it just clicked...sometimes it just takes another perspective..You truely have a gift..Thank you so much!

[@stevespassport]

I am currently taking A & P at a very respected college but if you were to offer online classes I would opt for your classes in a minute. I really appreciate the understandable way you present. Thank you for all your work. I think Glen Oaks would do well to offer an online program with you teaching. Sincerely, Steve

[@MsGemmaRichards]

Thank you very much, incredibly helpful in explaining in better detail than a 50 min class lecture!

[@carlaparsons1855]

Thank you for the excellent explanation. What really helps me is watching someone draw diagrams as they explain. Seeing a diagram that already exists is harder for me to understand. I really appreciate you taking the time to do this.

[@CoimbatoreCulturalClub]

Superb elusive limited words spoken by u sir. Thanks

[@dmarie1004]

I would just like to say THANKS!!! I go to a highly ranked university of california....but you make this SO much more clear and i wish i had you for a professor!

[@slayerA0D]

holy crap, thanks alot! test tomorrow and still didnt understand this, i love how all of this works now that i understand it, you rock man!

[@nhidizzle]

Everytime I have an exam coming up, I just type your name in the search bar, the topic I want to learn and bingo! So grateful for your videos!

[@tcstcyoung]

Great videos! I especially appreciated that you pointed out that the next video, sliding filament theory, picks up where this one left off. I am enrolled in a hybrid course on A&P and your videos have helped me where the course lacks in lecture material! Thank you for taking the time to make these.

[@kaustshroff381]

Thank you so much you made my life so much easier. Don't know why my Professor cannot draw it and explain it. Its probably what separates great Profs like you from duds like mine.

[@jdoll1212]

Exam tomorrow. You've explained everything I needed to know in a concise way. I get it now... can't thank you enough!!!

[@renhartung]

@MissShenava -- I'm not aware of any mitochondria in the synaptic cleft, however there are plenty of mitochondria inside of the presynaptic and postsynaptic cells. They are needed in order to have enough ATP to power exocytosis by the presynaptic membrane (exocytosis is a form of active transport). In the postsynaptic cell ATP is required by the sodium/potassium pumps that help set up and maintain resting potential. I'm sure there are more reasons, but those come to mind first.

[@bixwoof]

You literally saved my life! Thank you so much, I knew the basics but you just tied it all together so concisely and logically. My mind is blown! :)

[@tucho888]

You are an excellent teacher. Your help is invaluable. Thank you.

[@andrewdangg]

wayyyyyy better than my teachers. I can always trust youtube for my education. THANKS!

[@belOH8]

You've got a lot of comments saying the same thing, and you're about to get another one. Thanks so much for this, you have a very clear teaching style :).

[@gentlestormwyatt]

Amazingly explained. This helped for my final for tomorrow. Thanks

[@amandam1389]

I'm writing a short essay on excitation-contraction coupling and unfortunately was extremely confused & had no idea where to start -- there's a lot going on! Your explanation made it a lot clearer! Thank you!

[@mwilso9123]

Thank you so much for this video. I was getting scared I wasn't going to understand this lol, You broke it down and made it easy to understand and see what is going on. Thanks so much!

[@Lorgirl614]

This is an awesome explanation! I wish my instructor was so clear and concise as you! Thank you for helping me study for my test! :)

[@Ceironftw]

Best teacher of the world!!!

[@deegonzalez6475]

Thank you so much! I could hug you! You made this so clear and understandable! Please don't stop what you are doing, it has helped me tremendously!

[@renhartung]

Calcium ions are at higher concentration outside of cells. Cells tend to pump Ca++ outside of their membranes (and into their smooth endoplasmic reticulum). So, the fluid around the axon terminal is where the Ca++ comes from :)

[@leecohen291189]

thanks for the video! you are great! we are studying medicine and your videos have been very helpfull thanks again.. Elad gross and Lorraine fransis

[@renhartung]

Acetylcholine is a neurotransmitter for skeletal muscles (somatic motor pathways) but is also used in both sympathetic and parasympathetic innervation (autonomic motor pathways). Norepinephrine is a neurotransmitter that is used in the last step of a sympathetic autonomic motor pathway. Complicated enough for you :)

[@jenniferfoster246]

Thank you so much for the video's! They are great! I just draw and color along with your lecture...awesome way to learn.

[@marrrio14]

Oh goodness!!! Much better explanation than my physiology professors´ in medical school. Thanks a million!

[@churchboy19]

Your freaking awesome Im taking physio and micro right now and I must get A's for nursing but u are soooo clear thanks

[@mohammadshariqkhan9977]

Just awesome i am struggling with this topic and i pretty much confident about it for my final exam tommorrow..

[@XaticeFN]

Thank you! Very clearly and thoroughly explained, helped me study for my Anatomy final. I enjoy your videos!

[@pauldarlington317]

Thank you so much, God bless you and increase your wisdom sir.

[@mikulaskozar3404]

Great video. Better lecture, than from my biology teacher.

[@sensualberry69]

This was so awesome and helped me understand it much better than how my teacher taught it… thank you

[@SixxFootThree]

Dr. Hartung, after watching this video segment i'm guessing that Tetanus would also prohibit the breakdown of AcetylCholine in the Synaptic Cleft i.e. similar to your nerve gas example.

[@renhartung]

Yes, the Ca++ entering the axon terminal activates motor proteins involved with exocytosis of the neurotransmitter. If you want the details on how this works take a look at the wikipedia page on exocytosis.

[@deebee2142]

you sir are a God Send!! This really REALLY helps to rexplain what we've went over in class so that I really get it. Great study tool! I only wish I'd found you earlier lol!!

[@formosawest]

great video. would have liked a more thorough explanation... of course this is only partially complete/true. As this process differs slightly in cardiomyocytes vs skeletal muscle cells.. i was hoping for a description of cardio-selectivity in Calcium channel blockers, versus non-cardioselective dihydropyridines... and specifically how the excitation-coupling process differs in these two places... One is calcium induced calcium release at ryanodine channels (as is shown here) and the other is mechanical induced ryanodine channel calcium release. ...id like to know more about that please.. if you get a chance to expand on this topic. Andrew

[@alexandergugala6990]

You taught me more than my professor and my TA combined

[@cphuyel001]

Thanks you so much...you are better than my teacher

[@CamilaChannel]

Awesome thank you! I have one question.. which way does sodium and potassium rushes in and out? And how much of each?

[@renhartung]

Sodium rushes into the cell and potassium rushes out, there is no specific amount though. It's more about the charge changes that their movement creates. Take a look at videos that cover membrane potentials (resting potential and action potentials) to get a better idea of the importance of these ions.

[@CamilaChannel]

Thank you so much! Yes I was getting the resting and action potentials mixed up!

[@renhartung]

There is not really a relationship between Parkinson's disease and the neuromuscular junction. The tremors are actually initiated up in the brain where the actual problem appears to be. The only relationship to the neuromuscular junction is that motor areas of the brain are sending signals to those junctions leading to the tremors that the person experiences, but those signals appear to be due to an imbalance of neurotransmitters happening in those motor areas rather than at the junctions.

[@JackhammerNOR]

Hello! Is it possible to make a video of the t-tubule system? I heard you mention it in a video, but I can't find it explained.

[@deathnotelover11]

Thank you so much! You cleared it up for me. It's so easy now. (I been reading my textbook and I would get confused but now that I now how it works it's quite simple!)

[@mixermail]

THHHHHHAANNNKKK You!!!!!! Very detailed and easy to understand.

[@25zsams]

I have learned that acetylcholine is a parasympathetic neurotransmitter. then how come in this case, it stimulates contraction, which is sympathetic response? I am assuming that the muscle you drew is not a skeletal muscle. I m probably wrong, so... thanks!

[@hafizrustam8422]

god bless u with such a gud vedio i m really thankful to u

[@khadijaalbalushi4616]

Amazingly explained ...Thank U So much !

[@sukhrajhundal8444]

Absolutely amazing👍I understood everything now😊

[@medguard19]

Thank you Sir... wish you were my professor!!!

[@eg7737]

Thank you for helping me understand this.

[@marcelasafarova4625]

I like this video, it´s really helpful, but there is one thing I don´t understand and I can´t find how it works. What happend when Ca++ comes into axon, how it is possible that it starts exocytosis ?

[@glbxx]

Thankyou so much! This has helped me enormously. Wish you were my teacher :)

[@MissShenava]

There are mitochondria present in the synaptic cleft, why are mitochondria essential for for the transmission of impulses across the cleft for muscular contraction? Thanks

[@titislukita]

is there relationship between the neuromuscular junction with Parkinson's sufferers who experience tremors?

[@LarryJ27KC]

This was incredibly helpful. Thank you so much.

[@girishchaudhary2246]

Thanks sir.but i read the word acityle choline in place of serocholine so my que. is this two word same ya not? Please reply soon.

[@renhartung]

Acetylcholine (ACh) is the neurotransmitter. I've never heard of serocholine.

[@soulafkakel6871]

Thanks dr . but I would like ask you why you explained Ach? because as I knew that Ach has adifferent effect and oppist to catecholamine , this make me confuseed a little bit>

[@renhartung]

Sometimes ACh and catecholamines do have opposite effects (that is an accurate simplification for flight or flight responses for example), but not always. It's more complicated than that. Both ACh and epiniphrine can lead to depolarization of the target cell, to hyperpolarization of the target cell, or to other effects. It depends on the particular type of receptor the target cell has.

[@shuFFlerIam]

Where did the Ca++ in the motor neuron part come from? Thanks

[@melaniebatista6806]

Thank you so much! This helps a lot.

[@siraat-e-ishq]

How equilibrium potential of any particular ion achieved? Why the resting membrane potential is much close to Ex to Na ??

[@jackieee161]

Is norepinephrine the same as noradrenaline?

[@deja6819]

Is the resting potential not a -70mV? That is what I was taught. Just wondering.

[@renhartung]

Deja Garza The actual resting potential differs from one cell type to another: For neurons the resting potential is around -70 mV, but for skeletal muscle it is around -90 to -95 mV (at least in humans)... For the sake of your grade make sure you follow your textbook (or more importantly what your instructor says).

[@renhartung]

Nope, actually tetanus has its effects by a different mechanism. It damages motor neurons that send inhibitory signals affecting muscle contraction. Without the inhibitory signals muscles tend to stay contracted. Wikipedia has a good page on tetanus. Take a look if you have time.

[@skrozneobican]

Thank you professor!

[@myambition2313]

nice explanation. Thank you

[@rosapiie]

very well explained. thank you!

[@berkley102691]

once acetycholine is broken down how does it return back into the alpha motor neuron?

[@renhartung]

After the acetylcholine gets broken down by acetylcholinesterase what is left is acetate and choline. It looks like the acetate simply diffuses away into the surrounding tissue fluid, but the choline gets taken back up by the axon terminal (the same one that released the acetylcholine in the first place). The major mechanism for that re-uptake of choline is a system called "high affinity choline uptake system." Looking at the research papers I could find it looks like this high affinity choline uptake system uses the sodium gradient to pump choline into the axon terminal. This system is likely similar to the glucose/Na+ symporter (I read about this in --> Nature Neuroscience 3, 120 - 125 (2000)). I hope this helps, or at least gives you an idea of where to look.

[@saraloveee]

This was so helpful!

[@Whodatbuoy]

My right ear loved this

[@Pinkbun17]

I'm taking A & P in my third year in high school, and I gotta say this stuff is confusing! But thanks for explaining!

[@renhartung]

Yes, as I understand noradrenaline is another word for norepinephrine and vise versa :)

[@hotriffsofthrash]

Awesome vid thank you very much for this

[@renhartung]

There is no direct relationship between ACh and Ca++ that I am aware of. Take a look at my other video on the sliding filament theory to see where Ca++ comes into play in skeletal muscle contraction. You are correct about smooth muscle. For smooth muscle Ca++ comes into the cells from the outside during contraction. There is also other differences between skeletal muscle and smooth muscle contraction.

[@Tpainkiller21]

I thought the 90mv is the resting potential for nonexcitable cells..according to guyton's book the resting potential for excitable cells is about 70mv.

[@chelseafournier2255]

Soooo helpful, glad I found you're videos! Plus you're smokin hot!

[@lililankarani1307]

Thank you , that was really helpful.

[@renhartung]

Thank you. I was not aware of this. I looked up a few papers on it and it looks like the majority of fibers innervating eccrine sweat glands do use ACh. A good review can be found... Shebasaki, M. et al. Neural control and mechanisms of eccrine sweating during heat stress and exercise. American Physiological Society. 2006. PMID: 16614366

[@MsDellydell]

tq so much sir..u really help me a lot..

[@tehhometheatre836]

you sir are a godsend!

[@SixxFootThree]

I'm heading over to Wikipedia now. Thank you sir !

[@deshante2009]

Thank you!

[@AngieAPoku]

wow! a very nice video

[@ivonne3030]

thank you this really helps alot !!!!

[@cherry16pie08]

This was so helpful!! Thank you!!!

[@raquelcastillo6473]

Thank you so so so much!!!

[@leasfitfun]

amazing very helpful thank you!

[@emmaderth7692]

Thank you . im understand by this

[@sosnatemesgen3931]

Thank you so much

[@yellowtough]

Thx doctor!

[@ateneiyna5572]

Love this video!than you so much!!!!:)

[@TheCoope109]

Thank you!!

[@njose528]

one word: amazing

[@sakanablesakanable]

tHANK YOU SO MUCH...

[@purpleparadisex3]

what about threshold and domino affect?

[@renhartung]

+Kat Y I'm not sure what you mean by "domino affect" (unless you are talking about how an action potential moves along a cell) but I do describe what an action potential is in a video about neurons. The title of the video is "01 parts of the neuron with physiology." As far as I know the action potential that occurs in skeletal muscle cells is identical with the action potential that happens along the axon of a neuron.

[@hafizrustam8422]

what is the function of motor end plate

[@renhartung]

The motor end plate is a specialized region of the muscle cell's sarcolemma (muscle cell of the membrane) that is folded (postjunctional folds) and contains many acetylcholine (ACh) receptors (the motor end plate is also part of the neuromuscular junction. The motor end plate's function is to be very responsive to ACh so that whenever the motor neuron releases ACh the muscle fiber is stimulated and responds with contraction.

[@ludaludamartini2766]

Thanks!

[@yaseenme_]

9:23 for the rundown

[@hamzaabdullahi7920]

Thank you, you remind me of Walter White from breaking bad 😂👍