Flashcards in Cholinergic Agonists- T1 Deck (23):
The three classes of muscarinic agonists and examples
1. Ach derivatives: Ach, carbachol, bethanachol, methacholine
2. alkaloids: pilocarpine
3. synthetic- cevimeline
example of nicotinic agonist drug
cholinergic agonists have predominant actions on:
1. autonomic effector organs innervated by postganglionic parasympathetic nerves
2. cells containing cholinergic receptors.
cholinergic agonists primarily divided into:
1. Ach and synthetic choline esters
2. cholinomimetic natural alkaloids and analogs.
cholinergic agonists also activate__ found in
nicotinic receptors found in the ganglia, neuromuscular junction and CNS
-endogenous NT; no selectivity for muscarinic vs. nicotinic receptors
-rapid metabolism by Achesterase
-Ach is a (+) polar molecule, ester, that undergoes hydrolysis--> carboxylic acid and an alcohol.
derivatives of choline esters are generally
generally more resistant to AChE metabolism and have altered cholinergic receptor selectivity.
give the susceptibility to cholinesterase metabolism
Ach>methacholine> carbachol> bethanechol
activation of specific muscarinic receptors in various organs. (10)
decreases heart rate, vasodilation, increase intestinal smooth muscle contraction, motility, urinary( increased detrusor muscle contraction), increase bronchial constriction, increased salivation, increased salivation, increased mitosis, increased accommodation for near vision
What determines Gs/GI, GQ for signal transaction of muscarinic receptors
all receptors coupled to phosphoionsitide are
coupling of muscarinic receptors to effectors via GO/I
-M2 receptor activation results in decreased heart rate and decreased neurotransmitter release from cholinergic nerves.
-M2 receptors regulate cAMP by decreasing adenylyl cyclase activity. cAMP regulates heart rate and contractility.
Q activity of cardiac myocytes, also activate potassium channels, stimulating the depolarization of cardiac cells.
what drug(s) can produce mitosis during eye surgery and decrease intraocular pressure
Ach and carbachol. pupil constriction via M3 receptors.
what drug for airway hyperactivity test
methacholine--> causes constriction and increased resistance to airflow.
what drug for urinary urgency and increase GI motility
bethanechol. bethanechol increases tension on the bladder.
cholinergic agonist natural alkaloids are
more selective for muscarinic vs nicotinic receptors, pilocarpine is the only one of therapeutic value, and tend to give long duration of action.
pilocarpine cardiovascular effects
decreases heart rate and blood pressure
alkaloids smooth muscle effects
pupillary constriction, initial increase followed by a decreased intraocular pressure, decreased far vision, increase bronchial and GI muscle contraction, promote urination.
alkaloids exocrine gland effects
sweating, N/V, salivation, lacrimation.
therapeutic use of pilocarpine
describe chant and what type of drug it is
-partial agonist of the alpha2beta4 neuronal nicotinic receptor.
-activates the receptor at sub-threshold levels but prevents binding of nicotine.