THE PITUITARY BODY 



a constant auditory stimulus does not affect the periodicity 

 of the oestrous cycle (Browman, 1937). However, the au- 

 thor found that constant illumination might cause a per- 

 sistence of oestrous smears of the vaginal epithelium from 

 a few days to several weeks. Normal cycles of oestrus, as 

 would be expected, were present in animals bhnded by cut- 

 ting the optic nerves or enucleating the eyeballs. Either op- 

 eration caused a resumption of normal cycles in animals in 

 constant oestrus because of continuous illumination or pre- 

 vented the development of persistent oestrus in similarly 

 treated animals. '"* 



Mammals. — In this section, recently acquired general in- 

 formation concerning the gonadotropic hormones of the pitui- 

 tary body will be discussed. There will be no further con- 

 sideration of the effects of light on the secretion of gonado- 

 tropic hormones; these are referred to in the preceding section. 



I. Female mammals. — There is a number of new reports 

 chiefly concerned with the effects of hypophysectomy on the 

 female gonads.'^ Swezy (1936) has again affirmed that the 

 rate of ovogenesis is accelerated in the rat's ovary as a result 

 of hypophysectomy. However, degeneration of the follicle 

 appears after growth has proceeded to a depth of 6-8 rows 

 of cells. She pointed out that this is the sole example of a 



■■" See also Hemmingsen and Krarup (1937). 



'5 Lacassagne (1935) concluded that the cells of the pars glandularis and other 

 parts are quite insensitive toward radon or X-rays. His experiments were performed 

 in rabbits. Although he was able, by the insertion of a tube containing i mg. of 

 radium, to cause destruction of the gland for a distance of 1.5-1.8 mm. accompanied 

 by the characteristic secondary changes in the ovary in about a week, he doubted 

 that radiation of the pituitary has therapeutic possibilities so far as ovarian function 

 is concerned. Even after complete destruction of the pars intermedia and pars 

 neuralis together with destruction of two-thirds of the pars glandularis, ovarian 

 function is not affected. His estimate that adequate anterior pituitary secretion is 

 maintained by one-third of the pars glandularis agrees well with the estimates of 

 Aschner (dog) and Smith (rat). 



Newell and Pettit (1935) found that irradiation (X-rays directed toward each 

 temple in small doses for 5 weeks) led to improvement in the subjective symptoms 

 of two-thirds of a group of women with dysmenorrhea (26 patients). Sham irradia- 

 tion had the same effect in half the proportion of a group with similar symptoms 

 (i.e., in one-third of a group of 15 patients). 



[62] 



