Master deck. Flashcards
Nitroprusside
Vasodilator of vascular smooth muscle.
NO is released in bloodstream to cause vasodilation.
Hydralazine
Vasodilator targeting K+ channel on vascular smooth muscle.
K+ channel opens > hyper-polarization > arterial relaxation > BP decreased
Activates RAAS, increases heart rate via baroreceptors.
Interferes with Ca2+ homeostasis.
Safe for pregnancy, not good for monotherapy.
Minoxidil
Vasodilator targeting K+ channel on vascular smooth muscle.
K+ channel open > hyperpolarization > muscle relaxation > decreased BP > reflex increase in heart rate
Causes hair growth.
Safe for pregnancy.
Good for patients w. serious hypertension that almost need dialysis.
Sildenafil (viagra)
vasodilator that targets the phosphodiesterase that breaks down GNP and relaxes vascular smooth muscle
Inhibit phosphodiesterase > upregulate GMP > smooth muscle relaxation > vasodilation
Acetycholine
Inhibitor of ACh release/uptake.
Targets smooth muscle cells, is a vasodilator in all vascular beds.
Hemicholinium
Inhibits Na+ and choline transporter in presyn terminal, blocking choline reuptake and ACh synthesis.
Vesamicol
Targets the H+/ACh ATPase pump of the synaptic vesicles.
It inhibits the transport of ACh into vesicles, ultimately preventing ACh release.
Botulinum Toxin
Target ACh vesicles: inhibits ACh release from the presynaptic terminal.
Nicotine
Nicotinic ACh receptor agonist.
Nicotinic ACh receptor at NMJ and all autonomic ganglia, and brain.
ACh > ion pore opens > influx of Na+ and Ca2+ > depolarization > muscle contraction.
d-Tubocurarine
Targets nAChR at the NMJ
competitively blocking ACh > prolonged relaxation of muscles
Hypotension, respiratory muscle paralysis.
Can be overcome w. ACh esterase inhibitors.
Succinylcholine
NMJ nAChR
Noncompetitive, depolarizing blocker.
nAChR activation > prolonged desensitization at the receptor until the agonist disassociates
Short half life, rapid onset. AChE inhibitors don’t help because they INCREASE the ACh at the synapse and cause more desensitization.
Hexamethonium
Targets neuronal nAChR
Competitive antagonist, decreases PNS and SNS input at target tissues. Neuronal nAChR have increased sensitivity.
