Study on the mechanism behind adjuvant action of diethylethoxymethylene malonate enhancing the rectal absorption of cefmetazole and lysozyme.

Abstract

Diethylethoxymethylene malonate (DEEMM) and diethyl maleate (DEM) enhanced the rectal absorption of cefmetazole [an antibiotic] in rats when studies were carried out using in vivo, in situ rectal loop and in vitro rectal everted sac method. An increase of cefmetazole transport was found when concentration of nonprotein sulfhydryls in rectal tissue was decreased by the presence of either DEEMM or DEM in the study using in vitro everted sac method, and the enhancement of cefmetazole absorption by the coadministration of either DEEMM or DEM was suppressed by the treatment with dimercaprol; membrane permeability of rectal tissue, therefore, seems to be regulated by the concentration of nonprotein sulfhydryls in rectal tissue. There were differences between the action of DEEMM and the action of DEM. Enhancing action of DEEMM was suppressed by the presence of Ca2+ in microenema while action of DEM was not so influenced, and DEEMM enhanced the rectal absorption of lysozyme in rabbits but DEM did not.