THE EFFECT OF SULPHAMETHOXYPYRIDAZINE ON LIVER AND PLASMA LEVELS OF VITAMIN A IN RATS

Abstract

Long‐acting sulphonamides are highly bound to plasma proteins; the present study deals with the effects of this binding property upon a vitamin A compound also transported by plasma proteins. Sulphamethoxypyridazine was administered in rats either orally or by intraperitoneal injection. A significant fall in plasma vitamin A level and an increase in hepatic vitamin A concentration were observed. These results suggest an interference by sulphamethoxypyridazine with the transport of vitamin A, either through competition between the drug and vitamin A for binding sites of plasma proteins, or through altered secretion of the vitamin from the liver. 1977 British Pharmacological Society