GONADS AND THE PITUITARY BODY 



Hohlweg, 1934; Lipschiitz, 1934; Nelson, 1934; Clauberg and 

 Breipohl, 1935; and Wolfe, 1935)/-' 



Meyer, Leonard, Hisaw, and Martin (1930, 1932) were the 

 first to show that the administration of oestrin over a long 

 period (they injected 2-10 rat-units per day for 30-70 days) 

 lessened the gonadotropic potency of pituitary implants in 

 immature rats. The donors, which received oestrin, were 

 either young normal female rats or adult castrated and 

 spayed rats. The clearest evidence of a diminished gonado- 

 tropic potency was obtained by weighing the ovaries of the 

 rats used for assay. Those of animals receiving the pituitary 

 of oestrin-treated rats weighed 40-47 per cent less than the 

 ovaries of animals receiving pituitary tissue from non-in- 

 jected rats. Similar results were obtained by Bialet-Laprida 

 (1933) and Lipschiitz (1934). The latter author emphasized 

 the absence of a luteinizing effect by the pituitary of the nor- 

 mal male rats to which he had administered oestrin. 



As a result of the closer study of the effects of oestrin on the 

 pituitary, some investigators have concluded that it in- 

 creases the secretion (and storage?) of a luteinizing hormone 

 (Hohlweg, 1934; Lane, 1935; and Wolfe, 1935; Hohlweg and 

 Wolfe used large doses of "Progynon" or the benzoate [oes- 

 tradiol] of this preparation). In adult normal rats there ap- 

 peared an ovarian luteinization which, following shorter peri- 

 ods of treatment (200 rat-units daily for 8-15 days), was 

 demonstrated by an increase in the size of the corpora lutea, 

 without any change in the number. The injection of oestrone 

 also brought about the formation of corpora lutea in imma- 

 ture rats. In Hohlweg's experiments, implants of the pitui- 

 tary from oestrone-treated donors produced few or no corpora 

 lutea in the ovaries of immature rats. Lane, using "oestrin,"'''' 



« The repeated injection of oestrin into the female dog causes a reduction in the 

 size of the pituitary — especially of the pars glandularis (Kunde and others, 1931). 



'•'• 6.25 rat-units daily for 5-39 days. His rats were 22 days old when the injec- 

 tion of oestrin was begun. 



[153] 



