The specificity of antigonadotropic sera

Abstract

The original work of Collip and his colleagues on “antihormones” has been confirmed in its main features by many workers, and it is now clear that the prolonged injection of an extract containing a gonadotropic hormone into an animal of a different species leads to the recipient becoming insensitive to its effects. At the same time, the serum of the recipient acquires the power to neutralize the antigenic extract in test animals. Since gonadotropic extracts can be prepared from all animal pituitaries so far examined, and from the blood serum of pregnant mares and women, as well as from human placenta and urine of pregnancy, a wide field of specificity investigation is opened up. Several groups of workers have reported on the specificity of antigonadotropic substances, produced under varying conditions and in different species of animals. Collip and his co-workers (Collip 1934) showed that rats rendered refractory to gonadotropic extracts of non-human pituitaries may be sensitive to extracts of human urine of pregnancy. Fluhmann (1935a) produced in the rat an antiserum to human pituitary extract, which was found to neutralize not only the effect of the antigenic extract against which it was prepared, but also that of an extract of human pregnancy serum. It did not, on the other hand, prevent the action of sheep pituitary extract administered to immature rats. In a later paper, Fluhmann (19356) records the preparation of an antiserum to an extract of human pregnancy serum, which did not inhibit human or sheep pituitary extract.