Pharmacology Flashcards
Effects of parasympathetic stimulation - Cardiac
Decreased heart rate and AV conduction rate
Decreased contractility
Effects of parasympathetic stimulation* - Vascular
Vasodilation
*Vessels do not receive parasympathetic innervation; muscarinic ACh channels may be activated by ACh agonists
Effects of parasympathetic stimulation - Respiratory
Bronchoconstriction
Effects of parasympathetic stimulation - GI
Increased secretory and motor activity; relaxation of sphincters
Efffects of parasympathetic stimulation - GU
Relaxation of sphincters
Promotion of voiding (urination, defecation)
Effects of alpha 1 sympathetic stimulation - vasculature
Vasoconstriction of cutaneous and splanchnic vasculature - diverts blood from these areas
Effects of alpha 1 sympathetic stimulation - GU
Contraction of uretal sphincters, bladder and prostate; promotes continence
Ejaculation
Effects of Beta 1 sympathetic stimulation - Heart
Increased heart rate (positive chronotropy)
Increased conduction velocity at AV node
Increased contractility (positive inotropy)
Effects of B1 sympathetic stimulation - Kidney
Increased renin release causing elevation of BP
Effects of B2 sympathetic stimulation - Vasculature
Vasodilation of skeletal muscle vessels - shunts blood toward skeletal muscle
Effects of B2 sympathetic stimulation - Respiratory
Bronchodilation
Effects of B2 sympathetic stimulation - Eye
Increased aqueous humor production causing increased intraocular pressure
Effects of B2 sympathetic stimulation - GU
Uterine smooth muscle relaxation
Bethanechol - Mechanism
Parasympathetic agonist; synthetic analog of ACh
Atropine - Mechanism
Reversible, competitive inhibitor of ACh at muscarinic receptors
Edrophonium - Mechanism & Pharmacokinetics
Reversible, short acting inhibitor of acetylcholine esterase; indirect muscarinic agonist
Neostigmine - Mechanism & Pharmacokinetics
Reversible, intermediate to long acting inhibitor of acetylcholine esterase; indirect muscarinic agonist
Prazosin - Mechanism
Selective A1 antagonist
Propanolol - Mechanism
Nonselective B1 and B2 antagonist