Effect of a Nonionic Surface-Active Polymer on Passage of Hydrocortisone Across Rat Intestine In Vitro

Employing the Crane and Wilson everted sac technique, the passage of hydrocortisone cortisol—in micellar solutions of oxyethylated tertiary octylphenol polymethylene polymer (tyloxapol)—from the mucosal to the serosal side of the rat intestinal membrane was studied. It was determined that the mechanism by which cortisol passes across the membrane is that of diffusion. However, it was found that the relative rate of passage of cortisol dissolved in micellar solutions of tyloxapol is a function of concentration of the solubilizing agent used and is inversely proportional to the concentration of tyloxapol and viscosity of the solution tested.