G protein linked 2nd messengers

Question 1

sympathetic

Answer 1

A1 A2 B1 B2: QISS

A1: smooth muscle contraction, papillary dilator contration, increase intestinal and bladder sphincter contractio

A2: decrease sympathetic outflow, decrease insulin release, decrease lipolysis, increase platelet aggregation

B1: increase HR, increase contractility, increase RENIN release, increase lipolysis

B2: vasodilation, bronchodilation, increase HR, increase contractivity, increase lipolysis, increase insulin, decrease uterone tone, ciliary muscle relaxation, increase AQUEOUS humor production.

Question 2

Parasym

Answer 2

M1 M2 M3 = QIQ (KICK)

M1: CNS, enteric nervous system
M2: decrease HR and contractility of atria
M3: increase exocrine gland secretion (lacrimal, gastric), increase gut peristalsis, increase bladder contraction, bronchoconstriction, increase pupillary sphincter constriction (miosis), ciliary muscle contraction (accomodation)

Question 3

Dopamine

Answer 3

D1 D2 = SI (YES, pleasure)

D1: relaxes renal vascular smooth muscle
D2: modulates transmitter release, especially in brain

Question 4

Histamine

Answer 4

H1 H2 = QS

H1: increase nasal bronchial mucus production, contraction of bronchioles, pruritus, and pain

H2: increase gastric acid secretion

Question 5

Vasopression

Answer 5

V1 V2 = QS

V1: increase vascular smooth muscle contraction
V2: increase H2O permeability and reabsorption in the collecting tubule of the kidney

Question 6

Gq

Answer 6

Gq => phospholipase C => PIP2 =>
DAG (activate protein kinase C) and
IP3 (increases Ca2+ -> smooth muscle contraction)

Question 7

Gs, Gi

Answer 7

Gs activates and Gs inhibits

Adenylyl cyclase => ATP to cAMP => protein kinase A =>

Increase Ca2+ in heart
Blocks myosin light-chain kinase (smooth muscle)

Question 8

Autonomic drugs: cholinergic

Answer 8

Hemicholinium: blocks choline reuptake

Vasamicol: blocks ChAT, transfering ACh into vesicles

Question 9

Autonomic drugs: noradrenergic

Answer 9

Metyrosine: blocks from tyrosine to dopa

Reserpine: blocks transferring dopamine into vesicle

Guanethidine, bretylium: blocks NE release from vesicle

Amphetamine: induces NE release from vesicle

Cocaine, TCA, amphetamine: blocks reuptake from junction

Question 10

Noradrenergic nerve terminal regulation

Answer 10

Release of NE from a sympathetic nerve ending is modulated by NE itself, acting on presynpatic A2 autoreceptors, and by ACh, angiotensin II, and other substances.