DIFFERENTIAL REACTIVITY OF INDIVIDUALS AND THE RESPONSE OF THE MALE GUINEA PIG TO TESTOSTERONE PROPIONATE¹

Abstract

Many investigators have directed attention to the close relationship between the reactivity of tissues, sometimes referred to as sensitivity or responsiveness, and the degree of response to hormonal stimulation. The literature in which the subject is discussed has never been reviewed completely, but a few references will indicate something of the extent to which differences in reactivity influence endocrine function. Smith and Engle (1927) reported that the response of immature rats and mice to pituitary transplants increased with age; that in older animals fewer transplants were required to produce precocious sexual maturity. Bradbury (1944) and McCormack and Elden (1945) found an inherent seasonal variation in the sensitivity of the rabbit to pituitary extracts. Albright, Burnett, Smith, and Parson (1942) presented evidence that in certain clinical cases of idiopathic hypoparathyroidism the disturbance was not a lack of hormone, rather a resistance to it. Selye and Albert (1942) described a differential reactivity of the adrenal gland.