It is now clear that G-protein-coupled receptors can regulate programmed cell death (apoptosis) through a variety of mechanisms that are dependent on cell type and receptor subtype. Here we present evidence that the G(q/11)-coupled subtypes of the muscarinic receptor family (namely M(1), M(3) and M(5)-muscarinic receptor subtypes) are able to protect against apoptotic cell death. In particular ...

BACKGROUND Many neuromuscular blockers act as negative allosteric modulators of muscarinic acetylcholine receptors by decreasing affinity and potency of acetylcholine. The neuromuscular blocker rapacuronium has been shown to have facilitatory effects at muscarinic receptors leading to bronchospasm. We examined the influence of rapacuronium on acetylcholine (ACh) binding to and activation of ind...

The overproduction of β-amyloid (Aβ) fragments in transgenic APPswe/PS1dE9 mice results in formation of amyloid deposits in the cerebral cortex and hippocampus starting around four months of age and leading to cognitive impairment much later. We have previously found an age and transgene-dependent weakening of muscarinic receptor-mediated transmission that was not present in young (6-10-week-ol...

Muscarinic receptors in the spinal cord have been shown to mediate antinociception and alter blood pressure. Currently, there is much interest in identifying which muscarinic receptor subtypes regulate these functions. Toward that end, this study aimed to identify and localize the muscarinic receptor subtypes present in spinal cord using in vitro receptor autoradiography with [3H]-pirenzepine a...

Ligands that bind to the allosteric-binding sites on muscarinic acetylcholine receptors alter the conformation of the classical-binding sites of these receptors and either diminish or increase their affinity for muscarinic agonists and classical antagonists. It is not known whether the resulting conformational change also affects the interaction between the receptors and the G proteins. We have...

the central cholinergic system has been associated with cognitive function and memory and acetylcholine plays an important role during the early stages of memory consolidation. in this study, after training mice were tested with one way active avoidance procedure and retention were tested at 4, 8, 12, 16 and 24 hours of training and compared with non-shocked mice, in which it took 24 hours, a s...

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...