Effects of heat--stress in rats. II. Factor(s) responsible for reduced embroynic and/or foetal survival percentage.
High ambient temperature (34.4 C degrees and 60-65% relative humidity (RH failed to maintain optimum embryonic and/or foetal survival rate in ovariectomized pregnant rats given exogenous progesterone and oestrone injections. A still higher ambient environment (36.6 C degrees and 70-75% RH) did not affect the decidual cell response (DCR) in psuedo-pregnant rats. Heat stress did not result either in insufficiency or lack of progesterone and hence the latter two are not factors for the heat stress causing embryonic and/or foetal loss. The possibility of the failure of oestrone being converted to oestradiol or an intrinsic interference of RNA synthesis to be the factors responsible for embryonic and/or foetal loss caused by heat stress has been examined.
D000818:Animals; D002369:Castration; D003656:Decidua; D004970:Estrone / Q000008:administration & dosage*; D005260:Female; D005313:Fetal Death / Q000209:etiology* / Q000517:prevention & control; D006358:Hot Temperature / Q000009:adverse effects*; D006813:Humidity; D010053:Ovary / Q000502:physiology; D011247:Pregnancy; D011374:Progesterone / Q000008:administration & dosage*; D011555:Pseudopregnancy; D051381:Rats; D014599:Uterus / Q000293:injuries
D004970:Estrone; D011374:Progesterone