Date of Award
Doctor of Philosophy (PhD)
Sera raised in rabbits against adult rat kidney has long been known to be teratogenic when administered to pregnant rats at a time when the embryos are in the gastrulation stage. The main hypothesis postulated on the mode of action of teratogenic kidney antiserum is that the antibodies directly interfere with placental development and function; thus resulting in a nutritional deficit to the embryo. A nutritional deficit is believed to interfere with embryonic morphogenesis. To date no investigations have been performed on placental function and development.
In the present investigation, histological and histochemical techniques were used to study the effects of kidney antiserum administered to the pregnant rat on the development and function of the fetal placental structures.
The results of this study have demonstrated that both the visceral yolk sac and chorio-allantoic placentae were adversely affected. The effects of kidney antiserum on the visceral yolk sac is consistent with an interpretation of an inhibition of nutrient uptake. The development of the chorio-allantoic villi and the allantoic vasculature was markedly retarded. The effects of kidney antiserum on the fetal placental structures suggest that the embryo undergo a nutritional deficit.
Glycogen and protein content of the maternal placenta was also investigated. The glycogen content was significantly lower in experimental rats as compared to controls. However, this difference was not noted until 72 hours after the administration of the kidney antiserum. This was a time when the embryos were not very susceptible to teratogenic antiserum insult.
Localization of kidney antibodies was also performed. The antibodies were demonstrated to be present within the embryo proper, amnion, parietal yolk sac, chorion and allantois.
Numerous Feulgen positive necrospherules were also observed within the embryo proper within 12 hours after the administration of kidney antiserum.
The observations of the present study is thus consistent with the interpretation that the cause of kidney antiserum teratogenesis is an effect of kidney antibodies on placental function and development resulting in a nutritional deficit to the embryo and/or is a direct effect of kidney antibodies on the integrity of the cells of the embryo proper.
Both control and experimental trophoblast shells contained islets of cells. These islets, not previously reported in the literature, contained mitotic figures. It is suggested that these islets are the proliferation sites of the trophoblast shell.
Juurlink, Bernhard H.J., "The Effects of Tissue Antisera Injected in the Pregnant Rat on the Development and Function of the Placenta" (1975). Open Access Dissertations and Theses. Paper 3036.