GONADS AND THE PITUITARY BODY 



it appears to be, is not comparable to the liberation of the 

 secretion from the gland in situ. Probably the least objection- 

 able example of "hyperhormonization" may be taken from 

 experiments with animals living parabiotically. In the ex- 

 periment 9 ^ (parabiosis between a normal female and a cas- 

 trated male), the excess gonadotropic hormone secreted by 

 the castrated male's pituitary, added to that of the female's 

 pituitary, finally produces marked follicular growth and cys- 

 tic follicles with continuous oestrus.''" These changes, once 

 they appear, may persist for months. No "antihormone" is 

 produced to antagonize the effects of the hormone secreted 

 far in excess of the female rat's needs. 



The preparation of gonadotropic extracts of the pars glandu- 

 laris. — The gonadotropic hormones so far extracted from the 

 pars glandularis usually appear not to have been purified 

 even to the extent of separating them from each other (if we 

 adhere to the behef that there are perhaps several gonado- 

 tropic hormones). Therefore, the most that will be attempted 

 here is (i) to refer to authors who have prepared extracts,^' 

 sometimes in an effort to separate gonadotropic hormones,*^^ 

 and (2) to discuss some of the apparent chemical properties of 

 gonadotropic hormones. 



The initial extraction is most conveniently performed by 

 using acetone-desiccated and defatted pituitary in the form 

 of a powder. If whole glands are used, extracts may contain 

 considerable amounts of the pressor and oxytocic hormones 

 of the pars neuralis. Methods for removing these have been 



^° Similar or greater changes are observed after the removal of the female rat's 

 pituitary. 



*' Evans and Long (1921-22); Biedl, Evans and Simpson (1928); Hewitt, Reiss 

 and Haurowitz (1929); Wiesner and Crew (1930); Loeser (1930-31); Wallen- 

 Lawrence and van Dyke, Wiesner and Marshall (1931); Guyenot and others, Mar- 

 shall, Robson (1932); Aschheim, Evans and others, van Dyke and Wallen-Lawrence 

 (1933); Hill, Meyer and Fevold (1934); Selye and others (1935). 



'^Fevold and others (1931, 1933); Evans and others, van Dyke and Wallen- 

 Lawrence (1933); Bates and others, Dingemanse, Guyenot and others, Wallen- 

 Lawrence (1934). 



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