Advances in understanding the phosphoinositide cycle have helped unravel the chain of events initiated by muscarinic receptor stimulation. Hydrolysis of membrane phosphoinositides generates both diacylglycerol, an activator of protein kinase C, and inositol phosphates. In the nervous system, muscarinic receptors elicit a wide range of electrophysiological responses. Recent studies have made pro...

Muscarinic cholinergic receptors modulate dopaminergic function in brain pathways thought to mediate cocaine's abuse-related effects. Here, we sought to confirm and extend in the mouse species findings that nonselective muscarinic receptor antagonists can enhance cocaine's discriminative stimulus. More importantly, we tested the hypothesis that muscarinic receptor agonists with varied receptor ...

Muscarinic cholinergic receptors modulate dopaminergic function in brain pathways thought to mediate cocaine’s abuse-related effects. Here we sought to confirm and extend in the mouse species findings that nonselective muscarinic receptor antagonists can enhance cocaine’s discriminative stimulus. More importantly, we tested the hypothesis that muscarinic receptor agonists with varied receptor s...

Up to date, there are four pharmacologically characterized subtypes of muscarinic receptors (M1, M2, M3 and M4). In our study we have investigated muscarinic receptor subtypes in smooth muscle layers of human stomach. Isolated preparations of longitudinal and circular muscle layers from human stomach were used. Acetylcholine, bethanechol, carbachol, pilocarpine and AHR -602 produced concen...

It has been generally accepted that, of the five subtypes of muscarinic receptors (M(1)-M(5)), only the M(2) subtype is expressed in mammalian heart. This notion has recently been challenged by a series of reports indicating that mRNAs for some or all non-M(2) subtypes are also present in mammalian heart, in parallel with the M(2) mRNA. However, the quantities of relevant mRNAs reported to be p...

In brain stem slices from neonatal (postnatal days 0-4) CD-1 mice, muscarinic ACh receptors (MAChRs) increased rhythmic inspiratory-related and tonic hypoglossal nerve discharge and depolarized single hypoglossal motoneurons (HMs) via an inward current without changing input resistance. These responses were blocked by the MAChR antagonist 1,1-dimethyl-4-diphenylacetoxypiperidinium iodide (4-DAM...

Muscarinic receptors play an important role in secretory and vasodilator responses in rat salivary glands. Nitric oxide synthase (NOS) activity was found coupled to muscarinic receptor activation as well as to nitric oxide-mediated amylase secretion elicited by carbachol. Parotid glands presented a predominant M(3) and a minor muscarinic M(1) acetylcholine receptor population, though carbachol ...

This paper presents a literature review and the author's own investigations devoted to identifying the morphological organization of different subcortical structures and neurochemical processes involved in the (regulation of defensive behavior. The effects of intrahypothalamic injections of two cholinomimetic substances, carbachol and d-tubocurarine, on rage and fear reactions were explored. Al...