Pharmacological profiles of the subtypes of muscarinic cholinoceptors that mediate aggregation of pigment in the melanophores of two species of catfish.
Using selective antagonists, including pirenzepine, adiphenine, AF-DX 116, gallamine, and 4-DAMP, we attempted to characterize the muscarinic cholinoceptors on the melanophores of the translucent glass catfish Kryptopterus bicirrhis and the mailed catfish Corydoras paleatus. The M3 receptor-selective antagonist, 4-DAMP, potently inhibited the acetylcholine-induced aggregation of pigment in both species. It appeared, therefore, that the receptors that mediated the cholinergically evoked aggregation of melanosomes in these species were of the M3 muscarinic subtype.
Department of Biomolecular Science, Faculty of Science, Toho University, Chiba, Japan.
H
H
Hayashi
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R
Fujii
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002397:Catfishes / Q000502:physiology*; D005260:Female; D008297:Male; D008544:Melanocytes / Q000187:drug effects / Q000378:metabolism; D008547:Melanophores / Q000378:metabolism*; D018727:Muscarinic Antagonists; D010276:Parasympatholytics / Q000494:pharmacology; D010860:Pigments, Biological / Q000378:metabolism*; D011976:Receptors, Muscarinic / Q000378:metabolism*
D018727:Muscarinic Antagonists; D010276:Parasympatholytics; D010860:Pigments, Biological; D011976:Receptors, Muscarinic; D000109:Acetylcholine