Muscarinic Receptors and the Control of Glucose-Induced Electrical Activity in the Pancreatic β-Cell
There is ample physiological evidence for the presence of muscarinic acetylcholine receptors in pancreatic β-cells7,8,9,12. Stimulation of parasympathetic nerves can cause hypoglycemia and insulin release, an effect which may participate in the so-called cephalic phase of insulin secretion. Since the role of parasympathetic innervation in health and disease is not obvious, a more accurate characterization of this receptor may be of interest. The aims of the present work are to test whether muscarinic receptors may be directly demonstrated in pancreatic islets of mice as judged by binding of the muscarinic antagonist 3H-quinuclidinyl-benzilate (3H-QNB) and to study the effects of cholinergic agonists on glucose-induced electrical activity, in order to search for the ionic mechanisms involved in muscarinic action.
KeywordsPancreatic Islet Muscarinic Receptor Insulin Release Input Resistance Membrane Conductance
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