We measured pharmacologically isolated GABAergic currents from layer II/III neurons of the rat auditory cortex using patch-clamp recording. Activation of muscarinic receptors by muscarine (1 μM) or oxotremorine (10 μM) decreased the amplitude of electrically evoked inhibitory postsynaptic currents to about one third of their control value. Neither miniature nor exogenously-evoked GABAergic curr...

We investigated the role played by agonist-mediated phosphorylation of the G(q/11)-coupled M(3)-muscarinic receptor in the mechanism of activation of the mitogen-activated protein kinase pathway, ERK-1/2, in transfected Chinese hamster ovary cells. A mutant of the M(3)-muscarinic receptor, where residues Lys(370)-Ser(425) of the third intracellular loop had been deleted, showed a reduced abilit...

Muscarinic receptor stimulation in the hippocampus has been associated with inositol phospholipid breakdown. In other systems this leads to the formation of inositol trisphosphate and diacylglycerol, which promotes the activation of protein kinase C. Phorbol esters, which directly activate protein kinase C, exhibit high and specific binding in the hippocampus. This, along with the advantages of...

1. In an attempt to assess the structural requirements for the muscarinic receptor selectivity of hexahydro-diphenidol (hexahydro-difenidol) and hexahydro-sila-diphenidol (hexahydro-sila-difenidol), a series of structurally related C/Si pairs were investigated, along with atropine, pirenzepine and methoctramine, for their binding affinities in NB-OK 1 cells as well as in rat heart and pancreas....

Muscarinic acetylcholine receptor (mAChR), a member of the G-protein-coupled receptors (GPCRs) gene superfamily, has been shown to mediate the effects of acetylcholine on differentiation and proliferation in the CNS. However, the mechanism or mechanisms whereby mAChRs regulate cell proliferation remain poorly understood. Here we show that in vitro bFGF-expanded neural progenitor cells dissociat...

Muscarinic acetylcholine receptors in isolated rat pancreatic acinar cells have an apparent Mr of 88 000, which could be decreased to 46 000 by papain, as deduced by covalent binding of the specific alkylating agent [3H]propylbenzilylcholine mustard. Muscarinic receptors on papain-treated acinar cells retained the antagonist-binding site and both high- and low-affinity binding sites for the cho...

Emerging evidence indicates that muscarinic receptors and ligands play key roles in regulating cellular proliferation and cancer progression. Both neuronal and nonneuronal acetylcholine production results in neurocrine, paracrine, and autocrine promotion of cell proliferation, apoptosis, migration, and other features critical for cancer cell survival and spread. The present review comprises a f...

objective(s): in the present study, the effect of tissue incubation with propranolol on functional antagonism of zataria multiflora boiss (z. multiflora) at muscarinic receptors of tracheal smooth muscle was examined.  materials and methods: the effects of three concentrations of aqueous-ethanolic extract, 10 nm atropine, and saline on muscarinic receptors were tested on incubated tracheal smoo...

The chronotropic response of embryonic chick hearts to cholinergic agents is first clearly detectable on day 5 in ouo and full responsiveness develops by day 7. Muscarinic acetylcholine receptors in fully responsive 9day-old hearts specifically bind the muscarinic antagonist quinuclidinyl benzilate. Binding is blocked effectively by muscarinic agonists and antagonists but is poorly inhibited by...

Acute exposure to low concentrations of methylmercury (MeHg) causes a severe loss of intracellular calcium (Ca2+(i)) homeostasis, which apparently contributes to neuronal death of cerebellar granule cells in culture. We examined the role of muscarinic receptors in MeHg-induced Ca2+ dysregulation and cell death in rat cerebellar granule cells in vitro using fura-2 single-cell microfluorimetry an...