THE PITUITARY BODY 



lium. However, oestrogens are also known to cause hyper- 

 trophy of some of the male accessory organs. It is probable 

 that this is a direct effect, although an indirect action on the 

 testicular interstitial cells may be a participating cause. 



The effect of oestrogens on the secretion of follicle-stimu- 

 lating and especially luteinizing hormones has interested a 

 number of recent authors. Usually it has been concluded 

 that enhanced luteinizing effects or abnormally long persist- 

 ence of corpora lutea already formed may occur as a result of 

 the injection of an oestrogen. For example, in the adult 

 mouse, Clauberg (1936) reported that sterility for as long as 

 29 days occurred after the injection of one or two large doses 

 of "follicle-hormone." The sterility was attributed to an ab- 

 normal persistence and growth of corpora lutea which might 

 be larger than those of pregnancy. In the rat, ovarian hyper- 

 trophy following the injection of various oestrogens is due to 

 corpora lutea (Ellison and Burch, 1936; Mazer, Israel, and 

 Alpers, 1936). Ellison and Burch found that this effect could 

 be prevented by hypophysectomy. The same conclusion was 

 reached by Fevold, Hisaw, and Greep (1936) as well as Hohl- 

 weg and Chamorro (1937), so that it appears that oestrogens 

 increase the rate of secretion of luteinizing hormone by the 

 pituitary body." Hohlweg and Chamorro injected 117 of 

 oestradiol benzoate into immature female rats; the customary 

 appearance of corpora lutea after this treatment could be pre- 

 vented by hypophysectomy on the second day after injection 

 but not if operation was delayed to the fourth day. 



The experiments of Fevold, Hisaw, and Greep were de- 

 signed to detect changes due to injected oestrin, in the 

 amounts of follicle-stimulating or luteinizing hormone liber- 

 ated by the pituitary . After the injection of oestrin (0.1-4 

 R.U.), a constant dose of pituitary follicle-stimulating hor- 

 mone was administered. The increased ovarian weight, in 

 comparison with immature animals receiving no oestrin, was 



^7 Lipschiitz has again reported that oestrogens lower the luteinizing potency of 

 the adult male rat's pituitary (e.g., see Lipschiitz, Palacios, and Akel, 1936). 



[84] 



