Term
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Definition
| peripherally-acting sympathetic neuronal blockers that decrease availability of NE to its receptors |
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Term
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Definition
| drug that decreases uptake of intraneuronal DA & NE into storage vesicles, eventually depleting stored levels of NE and reducing the amount of NE released with each nerve impulse; in CV system, drug reduces BP by decreasing cardiac output & peripheral arterial resistance; used to treat primary forms of hypertension; replaced by newer antihypertensives but is much less expensive |
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Term
| Side Effects of reserpine |
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Definition
| sedation & mental depression due to transmitter depleting action on CNS nerve endings; other side effects: postural hypotension, bradycardia, fluid retention; also diarrhea, increased GI motility, & increased secretions due to exaggeration of unopposed parasympathetic activities |
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Term
| Mode of Inactivation of Reserpine |
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Definition
| unknown; although cleared quickly from circulation, drug has depleting action on NE vesicles which is irreversible & long-lasting beyond termination of drug |
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Term
| methyldopa & clonidine (Catapres) |
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Definition
| centrally-acting sympathetic neuronal blockers that stimulate alpha-2-adrenergic receptor sites in the brain & thus indirectly reduce sympathetic neuronal traffic from central sympathic vasomotor centers to peripheral CV organs |
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Term
| Centrally-Acting Adrenergic Neuronal Inhibitors |
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Definition
| alpha-2-receptor agonists that act more importantly at CNS sites like the vasomotor centers, decreasing sympathetic neuronal outflow from the CNS to periphery (heart, vessels, kidneys); have fewer orthostatic hypotensive symptoms & no help in treating Raynaud's; also, cause little to no decrease in exercise capacity |
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Term
| methyldopa (alpha-methyldopa) |
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Definition
| drug that is converted by the Dopa-->DA-->NE enzymes, allowing it to act as an alpha-2-adrenergic agonist in the central vasomotor centers, dampening outflow of sympathetic nerve activity to periphery (kidney, heart, BVs); causes decrease in renin release which decreases heart rate and cardiac output as well as decreasing arterial peripheral resistance; currently used to treat hypertension during pregnancy (no harm to fetus) |
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Term
| Side Effects of methyldopa |
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Definition
| drug can cause peripheral fluid retention & centrally-mediated dry mouth & sedation common to most central-alpha-2 agonists; also induces "autoimmune" disorders: hemolytic anemia via positive Coombs test; abnormal LFTs during first few weeks |
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Term
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Definition
| drug that is converted by Dopa-->DA-->NE enzymes & acts as an alpha-2 adrenergic agonist in central vasomotor enters, dampening outflow of sympathetic nerve activity; causes decrease in renin release, leading to decreased heart rate and cardiac output and arterial peripheral resistance; used to treat primary hypertension; requires very small dose and best absorbed transdermally via patch, thereby providing smoother BP control with fewer side effects; also used to treat: migraines, ADHD, hot flashes, PTSD; nicotine, alcohol, & morphine withdrawal; direct injection into spinal cord has analgesic effect |
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Term
| Side Effects of Clonidine (Catapres) |
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Definition
| drug can cause peripheral fluid retention, centrally-mediated dry mouth & sedation, DOES NOT have "autoimmune" disorders; also has less severe orthostatic hypertension symptoms & has little or no decrease in exercise capacity |
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