Autonomic phys Flashcards
M1
Gq–> IP3/DAG cascade –> increase intracellular Ca
Location: enteric nervous system, CNS
M2
Gi–> decrease cAMP
Location: heart (atria, SA, AV nodes), smooth muscle
M3
Gq–> IP3/DAG cascade –> increase intracellular Ca
Location: Glands, bladder, smooth muscle eye
IV injection muscarinic agonist cause paradoxical vasodilation bc M3 lead to release NO. Does not occur w/ atherosclerosis where will cause vasoconstriction
a1 (3 locations)
Gq–> IP3/DAG cascade–> increase intracellular Ca –> increase peripheral resistance/MAP
Location: pupillary dilator muscle–>mydriasis
urethral and prostatic sphincter–>contraction
smooth muscle–>vasoconstriction
a2 (4 locations)
Gi–>lower cAMP presynaptically–> prevent NT release
Location: CNS–>decrease sympathetic tone, lower BP
Pancreatic islets–> decrease insulin release
Adipose tissue–> decrease lipolysis
Ciliary body eye–>decrease aqueous humor production
B1 (2 locations)
Gs–> Increase cAMP–> increase intracellular Ca
Location: myocytes (SA/AV node)–> Increase contractility and HR
JG cells–> increase renin
B2 (5 locations not including lungs and vessels)
Gs–> Increase PKA–> relax smooth muscle, vasodilation, dilate airways
Adipose–> stimulate lipolysis
Liver–> increase gluconeogenesis
Pancreatic islets–> increase insulin release
Ciliary body eye–> increase aqueous humor production
Uterus–> relax smooth muscle
Tyrosine adrenergic neurons
Tyrosine transport to nerve ending–> Convert to L dopa–> dopamine–> transport into vesicle (VMAT)–> Convert NE
NET
NE reuptake
DAT
DA reuptake
D1
Gs–> increase cAMP–> Increase PKA–> smooth muscle relaxation
Low dose dopamine increase cAMP renal vasculature, increase GFR, renal blood flow, sodium excretion
Activates B receptors at low dose and a receptors high doses (think DBA)
D2
Gi
Location: CNS, important target for antipsychotics
