Competitive inhibition of renal transport of p-aminohippurate by other mono-substituted hippurates

Abstract

Competitive inhibition of PAH transport by hippurate substituted in the ortho-, meta-, or para-position by a methyl, fluoro, chloro, bromo, iodo, or nitro group has been studied with slices of rabbit kidney cortex. Meta-substituted hippurates are better inhibitors of PAH transport than are the corresponding para-substituted hippurates, which, in turn, are generally better inhibitors than the corresponding ortho-compounds. Within the meta- and para-series inhibitory effectiveness was directly related to the weight or bulk of the substituent group. An inverse relation was noted between the rate of transport and the capacity to inhibit PAH transport. No correlation was noted between inhibitory effectiveness and alteration of electron distribution on the benzene ring.