Abstract
The influence of rat serum, used as the vehicle for injection, on the potency of ovine, rat and human pituitary LH in the hypophysectomized rat prostate assay of Greep was examined. In all cases, rat serum augmented the prostatic response to LH. Rat serum was apparently effective in augmenting the prostatic response to ovine LH even when injected at a separate site. Human serum, used as the vehicle for injection, was effective in augmenting the prostatic response to rat LH and, to a slight but significant degree, human LH. The mere presence of rat serum was not sufficient to bring about the augmenting effect. Rather, a certain, undetermined, minimal volume of serum was necessary. Rat serum failed to augment the potency of ovine LH in the ovarian ascorbic acid depletion assay of Parlow.