THE EFFECT OF A CONVULSANT (BUTYL CROTYL THIOBARBITURIC ACID) AND AN ANESTHETIC (THIOPENTAL) ON THE SODIUM FLUXES IN TOAD BLADDER

¹ Case Western Reserve University School of Medicine, Department of Anesthesiology, Cleveland, Ohio

In the isolated toad bladder the convulsant and the anesthetic had similar effects on the serosa: decreased sodium permeability and increased sodium transport. They also produced apparent similar effects on sodium transport after bilateral application: small concentrations stimulated and higher concentrations progressively decreased short-circuit current. Here, however, they had different effects on permeability: the convulsant produced a dose-related increase in permeability; the anesthetic decreased permeability in the lower concentrations and increased permeability in the highest concentration. On the mucosa, the convulsant had no effect on short-circuit current, but increased permeability. Here the lower concentrations of the anesthetic decreased transport and permeability to the same degree, whereas the highest concentration decreased transport and increased permeability. However, the anesthetic always initially produced a transient, small increase in permeability. it is concluded that the serosa to mucosa flux takes place in two separate channels and that the two drugs have different effects on these channels.