Cholinergic receptor-regulation of potassium channels and potassium transport in human submandibular acinar cells.
The cholinergic receptor-regulation of K+ transport was studied in human submandibular glands. Acetylcholine stimulation 10 mumol/L results in an increase in membrane permeability (86Rb+ efflux) for, and a net efflux of, K+ ions from the glandular tissue. In the post-stimulus period, there is a net re-uptake of K+ ions into the tissue. Patch-clamp electrophysiological techniques were employed to demonstrate the presence of a large conductance K+ selective ion channel in the basolateral membranes of isolated human submandibular acinar cells. The patch-clamp results indicate that this voltage- and calcium-activated K+ channel operates to regulate the K+ permeability in both the resting and acetylcholine-stimulated acinar cells. We discuss the role of the K+ channel, K+ efflux, and K+ re-uptake in relation to stimulus-secretion coupling.
D000109:Acetylcholine / Q000494:pharmacology; D000368:Aged; D001693:Biological Transport, Active; D002463:Cell Membrane Permeability; D004594:Electrophysiology; D005260:Female; D006801:Humans; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D008564:Membrane Potentials; D008875:Middle Aged; D011188:Potassium / Q000378:metabolism*; D011950:Receptors, Cholinergic / Q000502:physiology*; D012964:Sodium / Q000378:metabolism; D013363:Submandibular Gland / Q000166:cytology / Q000378:metabolism*
D007473:Ion Channels; D011950:Receptors, Cholinergic; D012964:Sodium; D000109:Acetylcholine; D011188:Potassium