G protein-coupled receptors mediate cell responses to extracellular stimuli and likely function in the context of a larger signal transduction complex. Utilizing the third intracellular loop of a G protein-coupled receptor in glutathione S-transferase pulldown assays from rat brain lysates coupled with high sensitivity detection methods and subsequent functional studies, we report the identific...

Muscarinic acetylcholine receptors are common throughout the CNS. The predominant subtypes in the brain are positively coupled to phosphoinositide hydrolysis and have been found to modulate multiple conductances. Muscarinic receptor activation is most often observed to be excitatory because of suppression of various potassium conductances. Here it is reported that three distinct effects of musc...

Muscarinic acetylcholine receptors belong to a superfamily of structurally related proteins which possess seven transmembrane spanning regions and couple to G-proteins [1-4]. Thus far, five distinct muscarinic receptor subtypes (designated ml-m5) are known to exist based on recent molecular cloning studies [2, 5, 6]. Earlier knowledge of muscarinic receptor heterogeneity was based on binding an...

OBJECTIVE Postmortem studies have implicated the central muscarinic acetylcholine system in schizophrenia. However, central muscarinic receptor availability has not previously been studied in vivo. Using [I-123]iodoquinuclidinyl benzilate ([(123)I]IQNB) single photon emission computed tomography (SPECT), the authors sought to compare the muscarinic receptor availability in vivo in unmedicated p...

PURPOSE Muscarinic receptors are known to regulate several important physiologic processes in the eye. Antagonists to these receptors such as atropine and pirenzepine are effective at stopping the excessive ocular growth that results in myopia. However, their site of action is unknown. This study details ocular muscarinic subtype expression within a well documented model of eye growth and inves...

INTRODUCTION Decreased vascular responses to salivary gland stimulation are observed in Sjögren's syndrome patients. We investigate whether impaired vascular responses to parasympathetic stimulation and muscarinic receptor activation in salivary glands parallels hyposalivation in an experimental model for Sjögren's syndrome. METHODS Blood flow responses in the salivary glands were measured by...

Introduction: Recent studies suggest that glucocorticoids modulate memory reconsolidation. Moreover, cholinergic system is involved in memory reconsolidation. Since glucocorticoids interact with brain cholinergic system in modulating memory processing, we investigated whether glucocorticoid influences on the reconsolidation of emotionally arousing training depend on the cholinergic system...

A genomic clone encoding the gene for the mouse M1 muscarinic acetylcholine receptor has been isolated, placed under the control of the zinc-inducible mouse metallothionein promoter, and transfected into mouse Y1 adrenal cells. The receptor concentration was about 300 fmol/mg membrane protein in the absence of zinc and could be increased to 4000 fmol/mg membrane protein in the presence of incre...