THE PITUITARY BODY 



did anterior pituitary extract when their effects were com- 

 pared in immature rats; precocious ovulation, however, could 

 occur after the administration of either. A comparison of 

 the effects of prolan and anterior-lobe extract after injec- 

 tions continued up to lo days was also made by Fluhmann; 

 the results were different from those obtained by himself and 

 others in immature female rats injected only 5 days. For ex- 

 ample, the same total dose of prolan produced a greater 

 ovarian hypertrophy if distributed over 10 days instead of 5, 

 whereas the reverse was true of anterior pituitary extracts. 

 Collip, Selye, and Thomson (1935) found that prolan, but 

 not anterior pituitary extract, produced theca luteinization 

 and oestrus in female rats less than 18 days old. 



These investigators (1934) also offered another type of evi- 

 dence against the belief that prolan is secreted by the anterior 

 pituitary. They injected prolan repeatedly into female rats 

 until its effects progressively diminished and finally disap- 

 peared. They then administered anterior pituitary extract 

 and produced typical ovarian hypertrophy with luteiniza- 

 tion. They also performed experiments in which the order 

 of administration was reversed and obtained the same re- 

 sults. On the other hand, Fluhmann (1935) produced an 

 "anti-serum" by repeatedly injecting an extract of human 

 pituitary. This "anti-serum" prevented the gonadotropic 

 effects of both human pituitary extract and prolan but not 

 those of sheep pituitary extract. Unfortunately, Fluhmann 

 did not attempt to produce "anti-serum" by extracts of 

 other human tissues. 



Wallen-Uawrence and van Dyke (1931) found that about 

 the same dose of prolan was required to produce ovarian 

 hypertrophy in female immature rats and seminal vesicle 

 hypertrophy in males; anterior pituitary extract, however, 

 caused ovarian hypertrophy in much smaller doses than those 

 required to cause seminal vesicle hypertrophy. Similarly, 

 Engle (1932) and Schockaert (1933) found that prolan 



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