G-proteins and receptors Flashcards
Which type of G-protein matches with the receptor M1?
Gq
Which type of G-protein matches with the receptor M2?
Gi
Which type of G-protein matches with the receptor M3?
Gq
Which type of G-protein matches with the receptor Beta-1?
Gs
Which type of G-protein matches with the receptor Beta-2?
Gs
Which type of G-protein matches with the receptor Alpha-1?
Gq
Which type of G-protein matches with the receptor Alpha-2?
Gi
Activation of M1 receptor causes:
Stimulation of phospholipase C, causing increased acid secretion in stomach
Activation of M2 receptor causes:
Inhibition of adenylyl cyclase, causes potassium channels to open, causing a DECREASED HEART RATE
Activation of M3 receptor causes:
Stimulation of phospholipase C, causing contraction of bronchi (VISCERAL smooth muscle)
What effect does M3 receptor activation have of VASCULAR smooth muscle?
VASCULAR smooth muscle is indirectly relaxed by M3 receptor activation
What effect does M3 receptor activation have of VISCERAL smooth muscle?
VISCERAL smooth muscle contracts when M3 receptors are activated
Which type of stimulation (sympathetic or parasymathetci) acts on M1, M2 and M3 receptors?
Parasympathetic
Which type of stimulation (sympathetic or parasympathetc) acts on Beta-1, Beta-2, Alpha-1 and Alpha-2 receptors?
Sympathetic
The Gs protein activates Beta-1 and Beta-2 to stimulate what?
Adenyl Cyclase
Activation of Beta-1 receptor causes:
Increased heart rate and increased force of heart
Activation of Beta-2 receptor causes:
Relaxation of bronchial and vascular smooth muscle
Activation of Alpha-1 receptor causes:
Stimulation of phospholipase C, Contraction of vascular smooth muscle?
Activation of which receptor causes CONTRACTION of vascular smooth muscle?
Alpha-1
Activation of which receptor causes RELAXATION of vascular smooth muscle?
Beta-2
Activation of which receptor causes INDIRECT RELAXTION of vascular smooth muscle?
M3
Activation of which receptor causes CONTRACTION of VISCERAL smooth muscle?
M3
Activation of Alpha-2 receptor causes:
Inhibition of adenyl cyclase, causing inhibition of NA release
Which G-protein activates which two receptors to cause inhibition of adenyl cyclase?
Gi
M2 (parasympathetic) and Alpha-2 (sympathetic)
(M2 - Decreased HR because opens K+ channels)
(Alpha-2 - Inhibition of NA (noradrenaline) release)