Synthesis and release of acetylcholine in the rabbit kidney cortex.
Several cholinergic processes were demonstrated and partially characterized in rabbit kidney cortical minces: choline uptake, acetylcholine synthesis and calcium-dependent release. Minces took up labelled choline, acetylated it, and stored it in a pool that was not readily accessible to physostigmine-sensitive cholinesterase activity. [3H]Acetylcholine synthesis but not [3H]choline uptake was inhibited by the removal of sodium ions or incubation at 0 degrees C. The release of newly synthesized [3H]acetylcholine was increased by 300 mOsmol urea in a calcium-dependent manner, but not by potassium depolarization (300 mOsmol), vasopressin (10 microM), or bradykinin (10 microM). These results suggest that acetylcholine may be synthesized by non-neuronal rabbit kidney cortical cells and that this transmitter may be released in response to physiological levels of urea.
Evans
S
S
Department of Pharmacology and Therapeutics, University of Florida College of Medicine, Gainesville 32610.
Garg
L C
LC
Meyer
E M
EM
D000107:Acetylation; D000109:Acetylcholine / Q000096:biosynthesis* / Q000378:metabolism; D000818:Animals; D002021:Buffers; D002118:Calcium / Q000378:metabolism; D002794:Choline / Q000378:metabolism*; D002802:Cholinesterases / Q000378:metabolism; D046508:Culture Techniques; D007672:Kidney Cortex / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D010830:Physostigmine / Q000494:pharmacology; D011817:Rabbits / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D014508:Urea / Q000494:pharmacology
D002021:Buffers; D014508:Urea; D012964:Sodium; D010830:Physostigmine; D002802:Cholinesterases; D002794:Choline; D000109:Acetylcholine; D002118:Calcium