692 



PHYSIOLOGY OF GONADS 



cidence of congenital malformations asso- 

 ciated with vitamin E lack (Cheng, 1959). 

 In the test of a possible converse relation- 

 ship, estradiol-induced abortion in guinea 

 pigs was not prevented by vitamin E (Ingel- 

 man-Sundberg, 1958) . 



Fat-soluble vitamins incorporated in the 

 diet may be destroyed by oxidation of the 

 unsaturated fatty acids. To stabilize the 

 vitamins, the addition of diphenyl-p-phen- 

 ylenediamine (DPPD) to the diet has 

 proven successful, but recent studies show 

 that DPPD has an adverse effect on re- 

 production and thus its use in rat rations 

 is contraindicated (Draper, Goodyear, Bar- 

 bee and Johnson, 1956). 



Vitamin-hormone relationships in preg- 

 nancy have been studied with regard to 

 thiamine, pyridoxine, pantothenic acid, and 

 folic acid. Thiamine deficiency induced still- 

 births, subnormal birth weights, resorption 

 of fetuses, and loss of weight in the mother. 

 However, as in the case of protein defi- 

 ciency, pregnancy could be maintained with 

 0.5 fjLg. estrone and 4 mg. progesterone (Nel- 

 son and Evans, 1955). Estrone alone had 

 some favorable effect on the maintenance 

 of pregnancy in thiamine-deficient animals, 

 but it was less effective in protein-deficient 

 animals. 



Fetal death and resorptions as well as 

 serum protein and nonprotein nitrogen 

 (NPN) changes similar to those reported 

 for toxemia of pregnancy (Ross and Pike, 

 1956; Pike and Kirksey, 1959) were induced 

 by a diet deficient in vitamin Be . Adminis- 

 tration of 1 fxg. estrone and 4 mg. progester- 

 one maintained pregnancy in 90 per cent of 

 vitamin Be-deficient rats (Nelson, Lyons 

 and Evans, 1951). However, the pyridoxine- 

 deficient rat required both steroids to re- 

 main pregnant and in this regard resembled 

 the hypophysectomized animal (Nelson, 

 Lyoas and Evans, 1953). Nevertheless, a 

 hypophyseal hormone combination which 

 was adequate for the maintenance of preg- 

 nancy in the fully fed hypophysectomized 

 rat (Lyons, 1951) was only partially suc- 

 cessful when there was a deficiency of pyri- 

 doxine. An ovarian defect is suggested. 



The folic acid antagonist, 4-amino- 

 pteroylglutamic acid, will rapidly induce the 

 death of early implanted embryos in mice. 



rats, and man (Thiersch, 1954j . Removal 

 of folic acid from the diet or the addition 

 of x-methyl folic acid will induce malfor- 

 mations when low doses are given and re- 

 sorptions when high doses are given. Fur- 

 thermore, this effect is obtained even when 

 the folic acid deficiency is delayed until 

 day 9 of a rat pregnancy or maintained for 

 only a 36-hour period. A deficiency of 

 pantothenic acid will also induce fetal re- 

 sorption. The vitamin is required for hatch- 

 ing eggs (Gillis, Heuser and Norris, 1942). 

 In animals deficient in folic acid or in 

 pantothenic acid, estrone and progesterone 

 replacement therapy did not prevent fetal 

 loss, suggesting that the hormones cannot 

 act (Nelson and Evans, 1956). In the above 

 mentioned deficiencies replacement of the 

 vitamin is effective. However, vitamins 

 other than those specifically deleted may 

 provide replacement, thus ascorbic acid 

 seems to have a sparing action on calcium 

 pantothenate (Everson, Northrop, Chung 

 and Getty, 1954) . 



Pregnancy can be interrupted by altering 

 vitamins other than those discussed above, 

 but the hormonal aspects have not been 

 explored. Thus, the lack of choline, ribo- 

 flavin, and Bi2 will induce fetal abnormali- 

 ties and interrupt gestation (Giroud, Levy, 

 Lefebvres and Dupuis, 1952; Dryden, Hart- 

 man and Gary, 1952; Jones, Brown, Rich- 

 ardson and Sinclair, 1955; Newberne and 

 O'Dell, 1958) . Choline lack is detrimental to 

 the placenta (Dubnov, 1958), riboflavin 

 deficiency may impair carbohydrate use 

 (Nelson, Arnrich and Morgan, 1957) and/or 

 induce electrolyte disturbances (Diamant 

 and Guggenheim, 1957) , and Bjo spares cho- 

 line and may be concerned with nucleic 

 acid synthesis (Johnson, 1958). Excessive 

 amounts of Bio are not harmful. It is in- 

 teresting to note that uterine secretions and 

 rabbit blastocyst fluid are rich in vitamin 

 B]2 (Lutwak-Mann, 1956), but its presence 

 in such large amounts has not been ex- 

 plained. 



An additional substance, lithospermin, ex- 

 tracted from the plant, Lathijrus odoratus, 

 is related to hormone functioning; it is anti- 

 gonadotrophic when eaten by nonpregnant 

 animals and man. The feeding of this sub- 

 stance to prciiiiant rats terminated the preg- 



