The Physiological Effects of Extracts of the Hypophysis Cerebri and Infundibular Body

Injections of extracts of the hypophysis cerebri have been tested by Szymonowicz and by Oliver and Sch~ifer during the course of their well-known experiments upon the effects of extracts of the adrenal glands. Szymonowicz * states that in two experiments of this kind, made upon dogs, he obtained a slight fall of blood pressure and a quickening of the heart beat, just the reverse of the cardiac and vascular phenomena observed after injection of adrenal extracts. He concluded, therefore, that the physiological effects of extracts of the hypophysis cerebri are different from those caused by extracts of the adrenal glands, and, so far as can be gathered from his brief description, are much less marked. Oliver and Sch~er t obtained different results. In their hands extracts of the hypophysis caused usually a marked rise of blood pressure together with an augmentation of the force of the heart beat, results resembling those obtained from extracts of the adrenal body. T h e r e was, however, this difference, that the pituitary extracts, unlike the adrenal, caused no slowing of the heart beat. As these results are quite unlike those obtained from extracts of the thyroid body, the authors use them somewhat hastily, as appears from my experiments, to combat the prevalent view of a physiological relationship between the thyroid and the hypophysis cerebri. The contradictory results obtained by the investigators quoted suggested to me the desirability of making further experiments of the same nature upon this organ. The results of these experiments have been very uniform so far as the general effects of the extracts are concerned,