Autonomic Channels Flashcards
Heart
M2 = Gi –> inhibits adenylyl cyclase
- decreases HR
- decreases conduction velocity
- decreases atrial/ventricular contraction
Beta1 = Gs –> activates adenylyl cyclase
- Increases HR
- Increases conduction velocity
- Increases atrial/ventricular contraction
Lungs
M3 = Gq - Contracton of bronchi/bronchioles - secretions of submucosal glands Beta2 = Gs - Dilation of bronchioles
GI tract
M3 = Gq - motility/cramps in stomach - Contraction (diarrhea, involuntary defecation) of Small intestines M1 = Gq - Secretions of GI glands
Bladder
M3 = Gq - Contraction of detruser muscle - Relaxation of trigone/sphincter Alpha 1 = Gq - urinary retention - trigone/internal sphincter contract
Blood vessels
M3 = Gq
- Dilation except when damaged
Beta2 = Gs
- Vasodilation (decrease TPR, diastolic BP, afterload)
Alpha1 = Gq
- contraction of arterioles (increase TPR, increase afterload)
- contraction of veins (increase venous return, increase preload)
Eye
M3 = Gq
- contraction of sphincter muscle (miosis)
- Contraction of ciliary muscle (accomodation)
alpha1 = Gq
- radial contraction (dilation) of radial muscle of eye.
Pancreas
alpha2 = Gi
- decreased insulin secretions
Beta2 = Gs
- increases insulin release
Liver
Beta2 = Gs
- increase glycogenolysis
alpha1 = Gq
- increase glycogenolysis –> increase blood glucose lvls
Name the Gq
alpha1, M1, M3
- phospholipase C cleaves PIP2 to form DAG (activates Protein kinase C) and IP3 (increases intracellular Ca+)
Name the Gs
Beta1, beta2
–> activate adenylyl cyclase which produces cAMP that increase protein kinase A activity
Name the Gi
M2, alpha2, D2 (MAD 2)
- inhibit adenylyl cyclase so less cAMP is produced and less activity of PKA
Describe Nn and Nm
No second messenger
- activation of Na+/K+ channels
