Term
| What is the synthetic pathway of NE or epinephrine? |
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Definition
| Tyr --Tyr hydroxylase-> dopa --L aromatic aa decarboxylase-> dopamine --dopamine hydroxylase-> NE --PNMT-> epinephrine |
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Term
| What is the rate limiting step in NE synthesis? |
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Definition
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Term
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Definition
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Term
| What enzyme is needed for epinephrine synthesis? |
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Definition
| PNMT (phenylethanolamine N-methyltransferase) |
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Term
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Definition
| cocaine, tricyclic antidepressants |
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Term
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Definition
| myocardial, glial, and hepatic cells (among others) |
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Term
| What is the tissue distribution of MAO vs COMT? |
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Definition
| MAO: brain, liver, kidneys; COMT: liver, non-neuronal tissue |
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Term
| What are epi/NE and dopamine metabolized into? |
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Definition
| epi/NE -> VMA (3-methoxy-4-hydroxymandelic acid); dopamine -> HVA (homovanillic acid) |
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Term
| MAO metabolizes [nerve terminal/circulating] neurotransmitters while COMT metabolizes [nerve terminal/circulating] neurotransmitters |
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Definition
| MAO metabolizes nerve terminal nts; COMT metabolizes both nerve terminal and circulating nts |
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Term
| alpha1 receptor function?; post or presynaptic? |
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Definition
| postsynaptic; constriction/contraction, gluconeogenesis and glycogenolysis |
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Term
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Definition
| presynaptic autoreceptor; postsynaptic in CNS to modulate sympathetic outflow; platelet aggregation |
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Term
| beta1 receptor tissue distribution |
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Definition
|
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Term
|
Definition
| relaxation, gluconeogenesis and glycogenolysis |
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Term
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Definition
| increase free fatty acid production |
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Term
| alpha1 signal transduction |
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Definition
| increase IP3, PLA2/C/D, and Ca++ |
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Term
| alpha2 signal transduction |
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Definition
| decrease Ca++, cAMP, AC; increase K+ channel activation |
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Term
| beta1 signal transduction |
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Definition
| increase AC, cAMP, L-type Ca++ channels |
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Term
| beta2 signal transduction |
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Definition
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Term
| beta3 signal transduction |
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Definition
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Term
| D1 and D2 receptor functions |
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Definition
| D1: vasodilation of renal, mesenteric, and coronary vasculature; D2: modulates neurotransmitter release |
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Term
| alpha1 receptor selectivity |
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Definition
|
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Term
| alpha2 receptor selectivity |
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Definition
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Term
| beta1 receptor selectivity |
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Definition
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|
Term
| beta2 receptor selectivity |
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Definition
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Term
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Definition
| decreased responsiveness to drug during prolonged exposure that occurs rapidly; common with indirect-acting agonists; contributes to desensitization |
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Term
|
Definition
| loss of receptor function |
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Term
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Definition
| decreased responsiveness to drug that occurs over a long period of time |
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Term
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Definition
| loss of the number of receptors |
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Term
| What is the ultimate effect on HR, MAP, and TPR of a large, rapid IV infusion of epinephrine? |
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Definition
| mildly elevated HR, elevated MAP, markedly elevated TPR |
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Term
| What is the ultimate effect on HR, MAP, and TPR of a small, slow infusion of epinephrine? |
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Definition
| markedly increased HR, increased MAP, decreased TPR |
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Term
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Definition
| increase HR, FOC, CV, CO, oxygen demand |
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Term
| sympathetic effect on lungs?; mechanism? |
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Definition
| 1. bronchodilation (b2) 2. decreased mast cell secretion (b2) 3. decreased bronchial secretions (a1) |
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Term
| sympathetic effect on gut?; what receptors are involved? |
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Definition
| smooth m. relaxation (b2); sphincter contraction (a1) |
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Term
| sympathetic effect on uterus in late pregnancy?; via what receptor? |
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Definition
| inhibition of uterine contractions (b2) |
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Term
| sympathetic effect on free glucose, free fatty acids, renin, and insulin |
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Definition
| increase in free glucose, FFAs, and renin; decrease in insulin |
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Term
| AE of catecholamine+halogenated hydrocarbon |
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Definition
|
|
Term
| AE of beta blocker + catecholamines |
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Definition
| cerebral hemorrhage (from unopposed vasoconstriction) |
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Term
| Why is there a vagal reflex with NE and not with epinephrine? |
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Definition
| NE does not act on beta2 receptors whereas Epi acts on all alpha and beta receptors |
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Term
| effect of low dose dopamine |
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Definition
| D1-mediated vasodilation in renal, mesenteric, and coronary vasculature |
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Term
| effect of high dose dopamine |
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Definition
| b1-mediated increase in FOC and CO; no effect on HR |
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Term
| effect of too high doses of dopamine |
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Definition
| a1-mediated vasoconstriction |
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Term
| What is the rate limiting step in Ach synthesis? |
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Definition
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Term
| ligand-gated channels = ?; G-protein coupled receptor = ? |
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Definition
| ligand-gated = nicotinic; GPCR = muscarinic |
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Term
| distribution of Nn receptors |
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Definition
| ganglia, CNS, adrenal medulla |
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Term
| distribution of muscarinic receptors |
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Definition
| M1-brain, ganglia; M2-heart; M3-smooth m., glands, vascular endothelium; M4-brain; M5-brain |
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Term
| molecular mechanisms of muscarinic receptors |
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Definition
| M1, 3, 5: IP3, increase Ca++, NO for vascular endothelium; M2, 4: increase K+, decrease AC |
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Term
| parasympathetic effect on eye |
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Definition
| sphincter contraction and ciliary m. contraction -> miosis, near vision |
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