Inhibition of the active transport of sugars by the intestine in vitro. I. Action of dinitrophenol, cyanide and a quaternary ammonium compound

Abstract

A relation has been made between the concentrations of the respective inhibitors in their activity on the active transport of sugars through the everted intestine of the rat and their effect on the respiration of the tissue previously studied.

Dinitrophenol totally inhibits the acti­ ve transport at concentrations of io~5M, through its action on the oxidative phosphorylization. The same effect at io~4 M is due to respiratory inhibition.

Cyanide inhibits the active transport at concentrations similar to those which inhibit the respiration of the mucosa. Both processcs are already ccrtainly affected with CN“ 5 x 10-4 M.

The quaternary ammonium compound inhibits the active transport at a concentration of 1o-3 M, and seems to have some effect at 5 x ro-4 M, which also inhibits the respiration of the mucosa.