Thanks for the breakdown and thorough explanation. It truly helped. And while I'm no longer in the Army, hearing "let me orient you" made me crack a smile.
Clear presentation. Just the right pace. Learning has occurred! Talented, capable and knowledgeable instructor. Great teachers are few and far between. Thank you, Michael Bentley, PhD!
This video really helps a lot to visualize the depletion of Ach. But @ 7:27 the doctor says that Ach has to stay away from pseudo cholinesterase. He should have said that Ach should stay away from True Cholinesterase which is the one that metabolizes Ach.
Great video. I want to draw a parallel to succinylcholine: Is phase 2 block caused by desensitization of the presynaptic nicotinic receptors (rather than direct antagonism as seen with non-depolarizing agents)? I'm having a hard time understanding why this would only occur at high doses.
+ElenaRox1994 Because the army also deal with medicine. Actually the wars up trough the years has improved the surgical knowledge and skills that no hospital could ever experience. The military medical branch is a very important branch of the military.
what does the presynaptic nicotinic receptor do? you explain the blocker is competing there but what does it NORMALLY do... I feel like thats essential in understanding this, and you dont explain it. for that reason.. thumbs down you just say positive feedback mechanism.. what are you talking about specifically? -First Year medical student
+Ryan Brunner....... presynaptic it has acetylcholine a neuron transmitter which attach to post synaptic. the below one in the diagram to open a channel called na/k channel which lead to influx of sodium from out side to inside n efflux of potassium from inside to outside which lead to depolarization
PREsynaptic receptors move the next set Ach filled vesicles to the “front line” (the edge of nicotinic nerve for preparation) and when another action potential comes and stimulates Ca2+ influx (which destabilizes the proteins that hold the vesicles in place) the “front line” is ready for release into the synaptic cleft. I know this is 4yrs old but I thought this reply may be helpful for others in the future -SRNA
Ryan Brunner the other response is true for POSTsynaptic nicotinic muscle receptors NOT PRE-. When Ach is released not all diffuses time the motor end plate, a fraction bind to PRE (Pos Feedback Mech).
