Possible Interaction: Muscarinic Antagonists and Niacin

“ConclusionsThese findings indicate that a nicotinic antagonist can attenuate impairments in memory produced by a muscarinic antagonist.”

“Either effect of a nicotinic antagonist—to decrease scopolamine-induced increases in acetylcholine output or to decrease postsynaptic acetylcholine receptor activation—may mediate the negative effects on memory of muscarinic antagonists.”

“Pharmacological analysis in slice preparations revealed that photoactivation-induced depolarization of layer 1 GABAergic neurons was blocked by a nicotinic receptor antagonist, whereas non–fast-spiking layer 2/3 GABAergic neurons was blocked only by the application of both nicotinic and muscarinic receptor antagonists.”

“Bath applications of the muscarinic antagonist atropine inhibited nicotinic currents dependent on concentration (EC50=24.3 μmol·l−1).”

“The nicotinic antagonists mecamy-lamine, methyllycaconitine, dihydro-&bgr;-erythroidine, and the muscarinic antagonist atropine blocked the depressant effects of the respective agonists.”

“The simultaneous application of both nicotinic and muscarinic antagonists (10 mM mecamylamine and 1 mM atropine) eliminated the increase in catecholamine secretion induced by carbachol.”

“This suggests muscarinic or nicotinic cholinergic stimulation of the anterior substantia nigra can have behaviourally similar effects and, at the doses used here, the effects of nicotinic and muscarinic stimulation are additive.”

“A combination of subthreshold doses of nicotinic and muscarinic antagonist induced an increase in all the spectral components.”

“ Muscarinic stimulation enhanced nicotinic receptor-dependent secretion.”

“This effect of MCC to increase ACh release from rat hippocampus and frontal cortex was antagonized by the nicotinic antagonists dihydro‐β‐erythroidine and d‐tubocurarine, but not by α‐bungarotoxin or by the muscarinic antagonist atropine.”