Canine ileal chloride absorption: effect of carbonic anhydrase inhibitor on transport

Abstract

The rates of movement of chloride and water from ileal loops into blood (insorption) and from blood into ileal contents (exsorption) were determined in dogs by the use of radiochloride and deuterium. The transmural electrical potential was measured. The appropriate values then were applied to Ussing's equation. The data indicated that chloride is actively transported by the ileum of the dog. The addition of acetazolamide (Diamox) decreased the observed transport flux ratio of chloride to a value which was similar to the calculated value for passive transport. It was concluded that acetazolamide inhibited active transport of chloride. When acetazolamide was present, the insorption of chloride was decreased while the exsorption of chloride was not affected. Water transport was decreased in parallel with chloride transport. Determinations of carbon dioxide content of the luminal fluid during the tests suggested that the effect of acetazolamide on chloride and water insorption is not related to its carbonic anhydraseinhibiting action.