NUTRITIONAL EFFECTS 



687 



B. INFLUENCE OF NUTRITION ON THE RESPON- 

 SIVENESS OF FEMALE REPRODUCTIVE TISSUES 

 TO HORMONES 



1. Ovary 



a. Inanition. Marrian and Parkes (1929) 

 were the first to show that the quiescent 

 ovary of the underfed rat can respond to 

 injections of anterior pituitary as evidenced 

 by ovulation and estrous smears. Subse- 

 quently the ovaries of underfed birds, rats, 

 and guinea pigs were found to be responsive 

 to serum gonadotrophin (Werner, 1939; 

 Stephens and Allen, 1941; Mulinos and 

 Pomerantz, 1941b; Hosoda, Kaneko, Mogi 

 and Abe, 1956). A low calorie bread-and- 

 milk diet for 30 days did not prevent ovar- 

 ian response to rat anterior pituitary or to 

 chorionic gonadotrophin. In these animals 

 an increase in ovarian weight with repair 

 of interstitial tissue, as well as folhcle 

 stimulation and corpus luteum formation, 

 were observed (Rinaldini, 1949). Rats from 

 which food had been withdrawn for 12 

 days could respond to castrated rat pitui- 

 tary extract with an increase in ovarian 

 and uterine weight (Maddock and Heller, 

 1947). Nevertheless, differences in the time 

 and degree of responsiveness to adminis- 

 tered gonadotrophin were noted in rabbits. 

 Animals on a high plane of nutrition re- 

 sponded to gonadotrophin at 12 weeks, 

 whereas rabbits on a low plane of nutrition 

 responded at 20 weeks and fewer eggs were 

 shed (Adams, 1953). 



b. Protein. Protein or amino acid defi- 

 ciencies in the rat do not prevent a response 

 to administered gonadotrophin (Cole, Guil- 

 bert and Goss, 1932; Courrier and Raynaud, 

 1932) . However, the degree and type of 

 gonadal response is influenced by the diet. 

 Thus, immature female mice fed to 6 per 

 cent casein for 13 days exhibited only fol- 

 licular growth in response to pregnant mare 

 serum, whereas the ovarian response in 

 mice fed 18 per cent casein was suggestive 

 of follicle-stimulating and strongly lutein- 

 izing actions (Table 12.9). Furthermore, 

 the ovarian response was significantly less 

 after 20 days of nonprotein feeding than 

 after 10 days of depletion (Leathem, 

 1958a). Ovarian stimulation by a gonado- 

 trophin involves tissue protein synthesis 

 and thus the type of whole protein fed 



could influence the responses. Yamamoto 

 and Chow (1950) fed casein, lactalbumin, 

 soybean, and wheat gluten at 20 per cent 

 levels and noted that the response to gon- 

 adotrophin as estimated by tissue nitrogen 

 was related to the nutritive value of the 

 protein. The ovarian weight response to 

 chorionic gonadotrophin was less in rats 

 fed 20 per cent gelatin than those fed 20 

 per cent casein (Leathem, 1959b). Inasmuch 

 as the hypophysis may influence the gon- 

 adal response to injected hormone despite 

 the diet, hypophysectomized rats fed a pro- 

 tein-free diet for 5 weeks and hyophysecto- 

 mized rats on a complete diet were tested 

 for response to gonadotrophins. The re- 

 sponse to FSH was not influenced by diet, 

 but the protein-depleted rats were twice 

 as sensitive to interstitial cell-stimulating 

 hormone (ICSH), human chorionic gonado- 

 trophin (HCG), and PMS as the normal 

 rats (Srebnik, Nelson and Simpson, 1958). 

 Protein-depleted, normal mice were twice as 

 sensitive to PMS as fully fed mice (Lea- 

 them and Defeo, 1952 1 . 



c. Vitamins. In the female vitamin B 

 deficiencies do not prevent ovarian re- 

 sponses to gonadotrophin (Figge and Allen, 

 1942), but the number of studies is limited. 

 Be deficiency in DBA mice was associated 

 with an increased sensitivity of the ovary 

 to gonadotrophins (Morris, Dunn and Wag- 

 ner, 1953), whereas pyridoxine deficiency 

 in the rat decreased ovarian sensitivity, 

 especially to FSH (Wooten, Nelson, Simp- 



TABLE 12.9 



Influence of dietary protein and pregnant mare 



serum {PMS) on the mouse ovary 



(From J. H. Leathem, Recent Progr. Hormone 



Res., 14, 141, 1958.) 



