Purified cholera toxin added to the mucosal solution of rabbit ileum in vitro caused changes in ion fluxes and electrical properties after a 50 to 60 min lag period. Potential difference and short circuit current increased and tissue conductance decreased. In Ringer solution containing HCO3, the toxin caused net secretion of both Na and Cl. In HCO3 free solution, the toxin reduced net Na transport to zero and caused Cl secretion. No toxic effects were observed on Na fluxes in HCO3 Cl free solution or on Cl fluxes in Na free solution. The changes in net electrolyte fluxes are most easily explained by postulating that cholera toxin stimulates an electrically neutral process that transports NaCl and/or NaCHO3 from serosa to mucosa.
ASJC Scopus subject areas
- Physiology (medical)