Mechanism of adrenergic stimulation of anion secretion in cultured rat epididymal epithelium.
Primary monolayer cultures of the epithelial cells from the rat cauda epididymidis had a basal transepithelial potential of 1.24 +/- 0.11 mV, apical side negative, a short-circuit current (SCC) of 2.42 +/- 0.17 microA/cm2, and a transepithelial resistance of 503 +/- 29.6 omega/cm2. Epinephrine (0.23 microM) added to the basolateral side caused a rise in the SCC (inward flowing) that was partially reversed by addition of amiloride, 4-acetamido-4'-isothiocyanostilbene-2,2'-disulfonic acid (SITS), bumetanide, and acetazolamide to the basolateral side. In the absence of Cl or HCO3, the SCC response to epinephrine was reduced by 65 and 66%, respectively. Removal of K reduced the SCC response by 40%, whereas Na removal completely abolished it. A23187 and phorbol ester, 12-O-tetradecanoylphorbol-13-acetate (TPA), stimulated the SCC when added to the apical side. Addition of the Cl channel blockers, anthracene-9-carboxylate and 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB) to the apical side reduced the SCC in a dose-dependent manner. It is concluded that anion secretion by the epididymis shares common mechanisms with other Cl-secreting epithelia.
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid / Q000494:pharmacology; D000584:Amiloride / Q000494:pharmacology; D000818:Animals; D001639:Bicarbonates / Q000378:metabolism; D002034:Bumetanide / Q000494:pharmacology; D000001:Calcimycin / Q000494:pharmacology; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002478:Cells, Cultured; D004553:Electric Conductivity; D004822:Epididymis / Q000187:drug effects / Q000378:metabolism*; D004837:Epinephrine / Q000494:pharmacology; D004848:Epithelium / Q000378:metabolism; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D013566:Sympathomimetics / Q000494:pharmacology*; D013755:Tetradecanoylphorbol Acetate / Q000494:pharmacology
D001639:Bicarbonates; D002121:Calcium Channel Blockers; D013566:Sympathomimetics; D002034:Bumetanide; D012856:4-Acetamido-4'-isothiocyanatostilbene-2,2'-disulfonic Acid; D000001:Calcimycin; D000584:Amiloride; D013755:Tetradecanoylphorbol Acetate; D015056:1-Methyl-3-isobutylxanthine; D004837:Epinephrine