Abstract
The urinary excretion of sodium cyclamate (CHS-Na) in rabbits was accelerated by the simultaneous administration of phenylbutazone, and the excretion rate constant of CHS-Na increased in accordance with an increase in the dose of phenylbutazone. In the experiment of intestinal recirculating perfusion, phenylbutazone did not accelerate the intestinal absorption of CHS-Na in rabbits. And the competitive inhibitory effect of phenylbutazone on the binding between CHS-Na and bovine serum albumin was found in the equilibrium dialysis experiment. Accordingly, these results demonstrate that the acceleration of the urinary excretion of CHS-Na in the rabbits following simultaneous administration of phenylbutazone is attributed to the competitive inhibitory effect of phenylbutazone in the binding between CHS-Na and rabbit serum albumin.
