Bioelectric behaviour of intestinal wall in the earthworm Scherotheca sp

Abstract

Transmural potential difference (TPD) and short circuit current in the Scherotheca sp. intestinal wall in in vitro preparations have been studied, as well as their variations as related to ionic substitutions. Sodium ion seems to participate the most in the genesis of registered potential, so that its total substitution in the medium brings about the disappearance of the potential. Transmural potential relies on metabolic energy and is inhibited by N2, 2,4-DNP and CNK. Ouabain inhibits TPD only when present on the serosal side. This might indicate the existence on that side of a Na+ pump responsible for the active transport of the cation from mucosal.