Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
31 Cards in this Set
- Front
- Back
|
What specific parasympathetic receptors should you know? |
-nicotinic receptors
-muscarinic M1, M2, M3 receptors |
|
|
What specific sympathetic receptors should you know? |
-beta-1 and beta-2 adrenergic receptors
-alpha-1 adrenergic receptors |
|
|
Where are nicotinic receptors located? |
ganglia & NMJ |
|
|
Where are muscarinic M1 receptors located? |
autonomic ganglia |
|
|
Where are muscarinic M3 receptors located? |
smooth muscle/glands |
|
|
Where are beta-1 adrenergic receptors located? |
cardiac muscle |
|
|
Where are beta-2 adrenergic receptors located? |
smooth muscle |
|
|
Where are alpha-1 adrenergic receptors located? |
smooth muscle/vasculature |
|
|
What is the NT for nicotinic receptors? |
acetylcholine |
|
|
What type of receptors are nicotinic receptors? |
ion channels |
|
|
What happens when nicotinic receptors are activated? |
fluxes Na+ and Ca2+ down gradient (into cell) and causes depolarization |
|
|
Are nicotinic receptors fast or slow acting? |
fast compared to GPCRs |
|
|
What is the structure of muscarinic M1 and M3 receptors? |
seven transmembrane domains (7-TMD) |
|
|
What is the NT for M1 and M3 receptors? |
Ach |
|
|
What happens after Ach binds an M1 OR M3 receptor? |
-M1/M3 receptor is activated -the receptor activates Gq protein -which activates phospholipase C -which hydrolyzes something into DAG & IP3 -IP3 binds to receptor and leads to contraction of smooth muscle around a gland AND -stored calcium is released as free calcium
|
|
|
What is the secondary messenger for M1 and M3 receptors? |
IP3 (also DAG) |
|
|
Why is the release of free calcium by M1 and M3 receptor activation so important? |
for myosin/actin interaction leading to contraction |
|
|
What is the structure of M2 receptor? |
seven transmembrane domains (7-TMD) |
|
|
What is the NT for M2 receptor? |
Ach |
|
|
What does an activated M2 receptor activate? |
Gi protein |
|
|
What is the result of an activated Gi protein? |
1. potassium channel is opened!
2. decreases cAMP formation |
|
|
What is the result of an open potassium channel? |
positive charge leaves, leading to hyper polarization, which slows heart rate |
|
|
What are the components of the cardiac beta-1 adrenergic receptor signaling system? |
-G protein coupled beta 1 receptor -a. cyclase -Ca2+ channel -cAMP protein kinase -sarcoplasmic reticulum -contractile proteins |
|
|
What is the NT for beta-1 receptors? |
epinephrine or norepinephrine |
|
|
What are the cellular level consequences of cardiac beta-1 adrenergic receptor activation? |
cAMP protein kinase ends up being activated, phosphorylating 3 things:
1) Ca2+ channels 2) SR 3) contractile proteins |
|
|
What are the physiological consequences of cardiac beta-1 adrenergic receptor activation? |
the increase in intracellular Ca2+ results in positive:
1) inotropism - increase in force of heart contractions
2) chronotophism - increase in heart rate/frequency of contractions |
|
|
What are the consequences of smooth muscle beta-2 adrenergic receptor activation? |
-beta 2 receptor activation increases cAMP levels
-cAMP decreases intracellular Ca2+ and actin-myosin interactions, resulting in relaxation
(think more blood flow, preparing us for fight/flight, more perfusion into skeletal muscle) |
|
|
What are the consequences of smooth muscle alpha-1 adrenergic receptor activation? |
increases IP3 and DAG, leading to increases in Ca2+
(can provide more help to myosin/actin of smooth muscle so contraction can happen; allows us to control BP) |
|
|
What 2 receptors must generally be kept at a balance in vascular smooth muscle cells? What does this balance achieve? |
-beta-2 and alpha-1
-controls blood flow and allows us to do fight/flight
|
|
|
Where are M2 muscarinic receptors located? |
heart |
|
|
What is the structure of the M2 muscarinic receptor? |
7-TMD |
