THE PITUITARY BODY 



ministered pituitary tissue, whereas similar augmentation of 

 the action of extract of menopausal urine indicated the 

 amount of luteinizing hormone administered. The author 

 administered lo rat-units of oestrin daily for lo days. Pitui- 

 tary tissue in a constant dose of 3.5 mg. dissolved in o.i per 

 cent NaOH was always given, so that the results refer to the 

 concentration of a particular gonadotropic hormone. The ad- 

 ministration of oestrin to adult, spayed fen.ale rats brought 

 about a reduction in the concentration both of follicle-stimu- 

 lating hormone and of luteinizing hormone. ■^" Contrary to 

 the results of Fevold, Hisaw, and Greep, repeated injections 

 of oestrin into immature rats had no effect on the concentra- 

 tion of follicle-stimulating hormone present; however, Leon- 

 ard agreed that the amount of luteinizing hormone was re- 

 duced. It must be remembered that the pituitary body was 

 intact in the immature rats used by Leonard for assay — per- 

 haps constituting a further complicating variable. 



Allen and Heckel (1936) reported that pseudopregnancy 

 in the rabbit can be prolonged to 25 days after a sterile mat- 

 ing, provided that oestrin be injected; the authors gave no 

 data on the dosage used. Hidaka (1937) produced pseudo- 

 pregnancy in rabbits by injecting pregnancy-urine; large 

 doses of an oestrogen caused a prolongation of the condition 

 (5,000-10,000 international units of "Gynandol benzoate" 

 on alternate days). Klaften (1937) injected various doses of 

 oestrone (sometimes as much as 1,200,000 I.LI.) to produce 

 corpora lutea. No corpora lueta could be observed in infan- 

 tile or juvenile rabbits (doses as high as 150,000 I.U.).^' In 

 adult rabbits there was found, in addition to corpora lutea, 

 glandular cystic hyperplasia of the uterus with loss of sensi- 

 tivity to the oxytocic principle of the pars neuralis. Robson's 

 results (1937) raise the question of the site of action of an 



■*" Castration alone caused a marked increase in the concentration of follicle- 

 stimulating hormone (comparison with normal animals). 



■<' Mazer, Israel, and Alpers (1936) stated that mature ovarian follicles could be 

 produced by the injection of large doses of oestrogens into immature rabbits. 



186] 



