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Autonomics-1.7
Pharmocology-Autonomics1.7/NicotinicCholinergic
Question | Answer |
---|---|
name the 2 catagories of drugs to stimulate cholinergic receptors? | nicotinic and muscarinic like agents |
rapid onset excitatory effects. Blocked by ND ganglionic blocking agents: | Nicotine |
delayed onset excitatory effects. Blocked by atropine-like drugs | muscarine and methacholine and partly AchE inhibitors |
Nicotine, Lobeline, Epibatidine? | autonomic ganglia nicotinic agonist of no clinical use |
Succinylcholine? | NMJ nicotinic ag/antag, for skeletal muscle relaxation |
Hexamethonium? | autonomic ganglia nicotinic, antagonist of no clinical use |
trimethaphan? | autonomic ganglia nicotinic antagonist as a antihypertensive |
Tubocurarine, Pancuronium, Vecuronium? | NMJ nicotinic antagonist for skeletal muscle relaxation |
How do drugs affect the autonomic ganglia? | transient stimulation and then more persistant depression of ganglia (small dose facilitate transmission of impulses, large dose initial stimulation then very quickly a blockade) |
Nicotinic receptors in the adrenal medulla? | low dose evoke release of catecholamines, large dose prevent release |
nicotonic receptors in the NMJ? | similar to autonomic ganglia |
Nicotinic receptors in the CNS? | small doses are mildly alerting (tremurs), large dose are markedly stimulating (convulsions, excite respirations) large doses are followed by depression. Stimulate vomiting central and peripherial. |
nicotinic receptors in the CV system? | increase in HR and BP related to stimulation of sympathetic ganglia and adrenal medulla |
nicotinic receptors in the GI? | largely due to parasympathetic. Increase tone and motor of bowel. N/V, diarrhea following absorption of nicotine in niave person |
nicotinic receptors in Exocrine glands? | initial stimulation of salivary and bronchial secretion followed by inhibition |
nicotine pharmacokinetics? | absorbed readily, cig contains 8-9mg nicotine, 80-90% metabolized by liver. Cotinine is a major metabolite. 1/2 life 2 hours. Fatal dose is 60mg for an adult. |
what happens with nicotine poisoning? | N/V, salivation, abdominal pain, diarrhea, dizziness, confusion, weakness. Progress to hypotension, resp depression, convulsions, death |