CONICET | Buscador de Institutos y Recursos Humanos

Hypothyroidism is one of the most common endocrine abnormality implicated in the recurrent loss of pregnancy. In our laboratory, we have shown that hypothyroidism in the rat is associated with a lower number of pups per litter due to a lower number of implantation sites and a decrease in the proliferation (PCNA) of the endothelial and decidual cells during the process of implantation of the embryo. On the other hand, is known that angiogenesis is a critical process in the uterine endometrium for embryo implantation, maintenance of early pregnancy, and development of the placenta. During this period, steroid hormones (E2 and P4) stimulate the synthesis of vascular endothelial growth factor (VEGF-A), the main modulator of angiogenesis during peri-implantation period. Therefore we hypothetize that hypothyroidism affects the normal vascularizacion of endometrium during implantation. The aim of this work was to study the effect of hypothyroidism on the degree of vascularization of the uterine decidua during the implantation process. Hypothyroidism was induced in female Wistar rats bred in our laboratory by daily administration of 6-propyl-2-thiouracil (PTU) 0,1 g/L in drinking water. In addition, hormone replacement therapy with T3 was administered simultaneously to treatment with PTU, in daily physiological doses of 0,6ug/100g. On day five (G5) and seven (G7) of gestation, uterine vascularization was evaluated by immunofluorescence. Besides, mRNA expression of PECAM (Platelet endothelial cell adhession molecule, an indicator of the presence of endothelial cells) and VEGF-A was evaluated by RTqPCR during the same periimplantation periods (G5 y G7). Our results demonstrate that hypothyroidism decreases vascularization density of the uterine tissue during the process of implantation of the embryo (p