[Sodium 2,3-dithiopropanesulfate blockade of the effect of cholera enterotoxin on adenylate cyclase and the concentration of cyclic 3',5'-adenosine monophosphate in the small intestine mucosa of the rabbit].

Activation of adenylate cyclase in membrane preparations of the rabbit small intestine mucosa by cholera enterotoxin in the presence of sodium 2,3-dithiopropanesulfate (DTPS) is similar to that in the presence of dithiothreitol (DTT). Both DTT and DTPS do not influence the activity of adenylate cyclase without cholera enterotoxin. DTPS activates cyclic 3,5-AMP phosphodiesterase of mucosa homogenates (K0.5 = 10(-5) M). Combined administration of cholera enterotoxin and DTPS in situ into isolated loops of the rabbit small intestine decreases the activating effect of cholera enterotoxin on adenylate cyclase and diminishes the content of cyclic AMP in the mucosa. The destruction of disulfide bonds of cholera enterotoxin by DTPS is assumed to lower its ability to penetrate the mucosal cells of the small intestine.