Pharmacology Capstone Flashcards
Sympathetic Innervation to Cardiac and Smooth M
Preganglionic: ACh to nicotinic R
Postganglionic: NE to alpha and beta R
Sympathetic Innervation to Renal Vascular SM
Preganglionic: ACh to nicotinic R
Postganglionic: dopamine to dopamine R
Parasympathetic Innervation of Cardiac and Smooth Muscle
Long Preganglionic: ACh to Nicotinic R
Short postganglionic: ACh to Muscarinic R
M2 and M3 receptors
Smooth muscle mAChRs–M2 R is predominant cardiac M mAChR
End result of alpha 1 receptor activation
Muscle contraction
Activation of alpha 2 receptor
Vascular SM contraction, decreased insulin secretion, dec release of NE
Activation of beta 1 receptors
Inc force and rate of heart contraction
AV nodal conduction velocity
Activation B2 receptor
Vascular, bronchial, genitourinary, and GI SM to relax
Activation of of B3 receptor
Lipolysis
Alpha 1 receptor
- act thru Gq: inc PLC, IP3/DAG
- Epi>NE
- acts on vascular SM, GU SM, liver, intestinal SM
- responses: contraction, inc contractile force
Alpha 2 receptor
- Gi: dec adenylyl cyclase
- Epi>NE
- found presynaptically in CNS, dec insulin secretion, dec release of NE
Beta 1 receptor
- Gs: inc adenylyl cyclase
- Epi=NE
- heart: inc force of contraction
Beta 2 receptor
- Gs: inc adenylyl cyclase
- Epi>NE
- SM: relaxation
Beta 3 receptor
- Gs: inc adenylyl cyclase
- NE>Epi
- adipose tissue: Lipolysis
Innervation of Sweat Glands
Preganglionic: release of ACh to nicotinic R
Postganglionic: release of ACh to muscarinic R on sweat glands
Endothelium Derived Relaxing Factor
SM of blood vessels is not innervated by PS neurons but is innervated by sympathetic neurons
- blood vessel endothelial cells release a short lived vasodilator called EDRF, now known as NO
- in response to AP, PS neurons release ACh
- the circulating ACh activates mAChRs
- NO is produced by endothelial cells and diffuses back to SM cells surrounding blood vessels which it causes relaxation
Rule about alpha 1 adrenergic Rs
- stimulate contraction of all SM
- vascular SM–vasoconstriction
- glandular SM–secretion
Beta 2 adrenergic receptor Rule
- relax SM
- vascular SM–vasodilation
Muscarinic Rs rule
- contract SM
- NO acts on them to relax and vasodilate vessels
Parasympathetic Tone
Rest and digest
-cholinergic effects
Salivation Lacrimation Pupil constriction Dec in HR Urination Inc secretions Inc GI track motility
Sympathetic tone
Fight or flight
Adrenergic
Pupil dilation Inc in HR Urinary retention Dec secretions dec GI track motility
