Gonadotropic Hormones of the Hypophysis of the Turkey.

Abstract

E'rot)i t h p Zooloprccil L n b o r t r t o~y , Sttrtc University of Iowa.Relatively little \ I ork has been done in the past on the hypophysis of birds. Benoit' obtainetl evidence for the presence of gonadotropic hormones in hypophyses of sexually active ducks but not in those of inacti\-e ones. Similarly Riddle and Schooley2 found no effects from implanted hypophyses of pigeons less than 1.8 months old, while those of mature pigeons gave definite indication of the presence of some gonad stimulating principle. Since birds develop no true corpora lutea and differ also otherwise in their physiology of reproduction markedly from mammals, it seemed desirable to make a more complete. qualitative and quantitative analysis of their gonadotropic hormones.Through the courtesy of Mr. A. C. Gingerich, we were permitted to collect about 6000 hypophyses at the packing plant of the Maplecrest Turkey Farms at Wellman, Iowa. The glands were taken from birds about 6 months old, the hens weighing around 10 and the gobblers around 18 pounds. The fresh glands weigh about 13 mg. and 25 mg. respectively. However, the male glands lose more weight in the process of acetone-drying. One day's collection yielded 6.978 gm. dry powder from 1655 female glands and 9.900 gm. from 2047 male glands.The dry powder taken up in distilled water was assayed in 4 different tests. Table I gives the results obtained from injections into immature 21 day old rats. The largest dose (100 mg.) produces large ovaries which usually contain about as many corpora lutea as mature follicles. (However, in several cases the corpora were more numerous while in one case they were absent.) In the second group (50 mg.) the increase in ovarian weight is almost entirely due to the presence of many stimulated and mature follicles. A few incomplete corpora lutea are found in 3 cases. The third group (25 mg. ) has slightly increased ovaries that contain only few mature or distinctly enlarged follicles. However, sections through the vagina prove that enough estrogenic hormones were released to produce ~~ ~~ ~~ _ _~ -~ -~ ~ ~ Sided by grants from the Kationnl Research Council, Coixiniittee f o r Research in Problcnis of Sea.

Quantitative measurement by telemetry of ovulation and oviposition in the fowl

“…Gonadal maturation and ovdation are &Is0 d i r e c t l y controlled by the hypophyseal gonadotrophic hormones (29).…”

The Physiology and Pharmacology of the Pituitary Body.

“…The pituitary of birds contains gonadotropic hormone capable of stimulating the mammalian ovary fowl pituitary, ovulation in the rabbit, or ovarian hypertrophy in the normal or hypophysectomized rat; Witschi, Stanley, and Riley, 1937, turkey pituitary, ovarian hypertrophy in the normal or hypophysectomized rat). Leonard concluded that the fowl's pituitary contains luteinizing hormone as well as the hormone stimulating the adrenal cortex.…”