Ion transport by the intestine of the goby, Gillichthys mirabilis

1. 1. The posterior intestine of the seawater- and 5% seawater-adapted goby, Gillichthys mirabilis, in vitro generates a serosa-negative transepithelial potential. 2. 2. Net mucosal-to-serosal Cl flux exceeds net mucosal-to-serosal Na flux under short-circuit conditions. 3. 3. Short-circuit current is reduced after treatment with dibutyryl cyclic AMP or 3-isobutyl-1-methylxanthine, a phosphodiesterase inhibitor; Cl secretion was not stimulated. 4. 4. Regional differences in intestinal function are suggested based on differences in electrophysiological characteristics of middle and posterior intestinal segments.