title: Regulation of goby intestinal ion absorption by the calcium messenger system.
abstract: The role of the calcium messenger system in the regulation of ion absorption across the teleost intestine was studied using pharmacological intervention. Radiochloride transport was independent of external Ca2+ over the range 10 microM to 2.5 mM. Treatment with the Ca2+ ionophore A23187 (to hyperpolarization of the apical membrane potential of intestinal epithelial cells. The Ca2+-calmodulin antagonists trifluoperazine (TFP) and calmidazolium (R24571) produced opposite effects, i.e., stimulation of Cl- absorption and cellular depolarization. Treatment with TFP or R24571 will block or override the inhibitory action of A23187. These data suggest a regulatory role for Ca2+ in the control of intestinal NaCl absorption and mediation via calmodulin.
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology / Q000502:physiology*; D002147:Calmodulin / Q000037:antagonists & inhibitors; D005260:Female; D005399:Fishes / Q000502:physiology*; D007093:Imidazoles / Q000494:pharmacology; D007408:Intestinal Absorption / Q000187:drug effects; D007473:Ion Channels / Q000378:metabolism*; D008297:Male; D008854:Microscopy, Electron; D014268:Trifluoperazine / Q000494:pharmacology
chemical_list: D002147:Calmodulin; D007093:Imidazoles; D007473:Ion Channels; D014268:Trifluoperazine; D000001:Calcimycin; C031938:calmidazolium; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine