G Protein linked second messengers Flashcards
Which receptors are Gs proteins coupled to?
B1, B2, D1, H2, V2
Which receptors are Gi proteins coupled to?
a2, M2, D2
Which receptors are Gq proteins coupled to?
a1, M1, M3, H1, V1
Which sympathetic receptors are G-protein coupled?
alpha1, alpha2, B1, B2
What is the effect of activation of alpha 1 receptors? Which G protein is associated?
1) Inc vasc smooth muscle contration
2) Inc pupillary dilator muscle contraction (myriasis)
3) Inc intestinal and bladder sphincter muscle contraction
G protein: Q
What is the effect of activation of alpha 2 receptors? Which G protein is associated?
1) Decreased sympathetic outflow
2) Decreased insulin release
3) Decreased lipolysis
4) Inc platelet aggregation
5) Decrease aqueous humor production
G protein: i
What is the effect of activation of beta 2 receptors? Which G protein is associated?
1) Vasodilation
2) Bronchoconstriction
3) Inc Lipolysis
4) Inc insulin release
5) Decrease uterine tone (tocolysis)
6) Ciliary muscle contraction
7) Inc aqueous humor production
G protein: S
Which of the parasympathetic receptors are G-protein coupled?
M1, M2, and M3
What is the effect of activation of M1 receptors? Which G protein is associated?
CNS, enteric nervous system.
G protein: q
What is the effect of activation of M2 receptors? Which G protein is associated?
1) Decrease heart rate
2) Decrease contractility of atria
G protein: I
What is the effect of activation of M3 receptors? Which G protein is associated?
1) Inc exocrine gland secretion (lac/saliv/gastricacid)
2) Inc gut peristalsis
3) Inc bladder contraction
4) Bronchoconstriction
5) Inc pupillary sphincter muscle contraction (miosis)
6) ciliary muscle contraction (accomodation)
G protein: M3
What is the effect of D1 receptor activation? Which G protein is associated?
1) Relaxes renal vascular smooth muscle
G: S
What is the effect of B1 receptor activation? Which G protein is associated?
1) Inc heart rate
2) Inc contractility
3) Incr renin release
4) Incr lipolysis
G protein: S
What is the effect of D2 receptor activation? Which G protein is associated?
Modulates transmitter release, especially in brain
G protein: i
What is the effect of H2 receptor activation? Which G protein is associated?
1) Inc gastric acid secretion
G protein: S
What is the effect of H1 receptor activation? Which G protein is associated?
1) Inc nasal and bronchial mucus production
2) Inc vascular permeability
3) Contraction of bronchioles
4) Pruritis, Pain
G protein: Q
What is the effect of V1 receptor activation? Which G protein is associated?
Inc vascular smooth muscle contraction
G protein: Q
What is the effect of V2 receptor activation? Which G protein is associated?
Inc H2O permeability and reabsorption in collecting tubules of kidney (V2 in the 2 kidneys).
G protein: S
