OVARY AND THE ANTERIOR PITUITARY BODY 165 



Since recent detailed work on the relation between the 

 anterior pituitary body and the ovary has been largely con- 

 cerned with the production of ovulation, the following 

 account will be restricted to this aspect of the problem. 



{e) ASSAY OF ANTERIOR PITUITARY EXTRACTS 



It is essential that anterior pituitary extracts should be tested 

 on the intact animal, as contrasted with oestrin which must be 

 assayed on the ovariectomized animal. The effects of oestrin 



a 



c d 



Fig. 62. — Effect of CEstrin and anterior Pituitary 

 Extracts on Uterus and Ovary of young Mouse. 

 {a) Normal; (6) oestrin — action on uterus only; (c) implants of 

 anterior pituitary — action on ovary and thence on the uterus; {d) 

 NaOH extract of anterior pituitary — action on ovary only. 



and anterior pituitary on the intact immature animal are 

 superficially similar, i.e. the production of precocious oestrus. 

 Actually, of course, the result is quite different. CEstrin, acting 

 directly on the accessory organs, causes the reaction in the 

 ovariectomized animal; anterior pituitary preparations, 

 primarily affecting the ovary, will act only on the intact animal. 

 When testing for the anterior pituitary substance in fluids 

 which might contain oestrin {i.e. the urine of pregnancy), 

 Aschheim and Zondek (39) give a control dose to ovariecto- 

 mized animals, and, if this is negative, test again on intact 



