Nicotinic Signaling Stimulates Glucagon Secretion in Mouse and Human Pancreatic α-Cells.

Smoking is widely regarded as a risk factor for type 2 diabetes because nicotine contributes to insulin resistance by desensitizing the insulin receptors in muscle, liver, or fat. Little is known, however, about the immediate regulation of islet hormonal output by nicotine, an agonist of ionotropic cholinergic receptors. We investigated this by imaging cytosolic Ca2+ dynamics in mouse and human islets using confocal microscopy and measuring glucagon secretion in response to the alkaloid from isolated mouse islets.

Sleep. 1: Obstructive sleep apnoea/hypopnoea syndrome: definitions, epidemiology, and natural history.

Arguments over the definition of obstructive sleep apnoea/hypopnoea syndrome (OSAHS) have still not been satisfactorily resolved. As a result, robust estimates of the prevalence of OSAHS are not possible. New approaches are needed to identify those who have "CPAP responsive" disease, enabling more accurate estimates to be made of the prevalence of the sleep apnoea syndrome in the community.