Suppression of prolactin and thyrotropin secretion in the rat by antiserum to thyrotropin-releasing hormone.

Administration of antiserum to synthetic thyrotropin-releasing hormone (TRH) to male and female rats cause a 50% and a 70% suppression in serum levels of prolactin and thyrotropin, respectively, as compared with controls injected with normal rabbit serum. The degree of suppression was similar in diestrous and proestrous female rats and in male rats. These findings support the view that, in addition to its original designation, TRH also has a physiological role in regulating release of pituitary prolactin.