[Problems of assessing the biological value of prostaglandin in vitro (author's transl)]

Isolated rat stomach strips were used to study the antagonism between psychotropic drugs and prostaglandin. It was found that the inhibited prostaglandin effect registered under the influence of psychotropic drugs in due not so much to the inhibition of synthetase action but rather to an inhibitory action on liberated prostaglandin. An atropine-like effect of the psychotropic drugs or an inhibition in the formation of endogenic prostaglandin in the walls are ruled out as possible explanations. The following possible explanations were discussed: a) the tested psychotropic drugs block prostaglandin receptors in the stomach; b) the test substances react with prostaglandin in the nutritive solution; c) the substances stimulate metabolic processes in the stomach wall that break down prostaglandin.