It has been suggested that toxicity to cocaine is related to the relative rate of cocaine metabolism by cholinesterases and to activation of cholinergic receptors either directly or by reflex mechanisms. We examined these possibilities by altering cholinesterase activity and blocking cholinergic receptors in rats prone or resistant to cocaine-induced cardiovascular toxicity. Rats were instrumen...

Exogenous acetylcholine (ACh) is known to stimulate atrial natriuretic peptide (ANP) secretion concomitantly with a decrease in atrial pulse pressure. However, the role of intrinsic ACh in the regulation of ANP secretion remains unknown. Recently, it was shown that nonneuronal and neuronal ACh is present in the cardiac atria. From this finding we hypothesize that endogenously released ACh is in...

Previous studies have demonstrated that N-methyl-D-aspartate (NMDA) receptors and acetylcholine receptors are related to learning and memory in rat and mice. In this study, we examined the effects of MK-801, a non-competitive NMDA receptor antagonist, on learning and memory in zebrafish using a passive avoidance test. We further tested whether or not nicotine, a nicotinic acetylcholine receptor...

Some studies have shown that acetylcholine muscarinic receptors involved in the opiate reward. In the present study, the effect of intra-basolateral amygdale (BLA) acetylcholine muscarinic like receptor agonist (physostigmine) and antagonist (atropine) on the acquisition of morphine-induced place preference has been investigated in male Wistar rats. For this purpose, two 22 gauges guide cannula...

Effects of stress on drug-induced yawning: Constant vs. intermittent stress. PHYSIOL BEHAV 58(1) 181-184, 1995.--Experiment 1 tested whether chronic exposure to immobilization, foot shock or forced swimming would result in suppression of apomorphine-, pilocarpine-, and physostigmine-induced yawning. Immobilization caused suppression of yawning, whereas foot shock and swimming resulted in increa...

This section (‘OfltWns 1) nett’ research findings, including preliminary data from pilot studies, cit/icr (Iini(’al or laboratory: 2) ;t’ortiitt’hile replication studies: 3) (‘uSe reports that describe a trim/v neit’ syndrome or (‘(1st nett’ light on established ones: and4) case reports that indicate a nett’ therapeutic pro(’edure ofpotential value or ‘all attention to adverse e.ff’ets o.fdrugs...