ALTERATION ON VASCULARIZATION AND PROLIFERATION OF THE UTERINE DECIDUA DURING THE PERIOD OF EMBRYO IMPLANTATION IN HYPOTHYROID RATS

TRONCOSO MARIANA; ESTEFANÍA RINALDINI; EZQUER M.E.,; CARLOS GAMARRA LUQUES; HAPON M. BELÉN

Villa de Merlo

Congreso; Sociedad de Biologia de Cuyo 2017; 2017

Sociedad de Biología de Cuyo

Several endocrinological abnormalities such as hypothyroidism have been implicated in recurrent pregnancy loss. In our laboratory, we have shown that hypothyroidism is associated with a lower number of pups per litter with no alteration in ovulation rate. Angiogenesis is a critical process in the uterine endometrium in preparation for embryo implantation, maintenance of early pregnancy, and development of the placenta. During this period steroid hormones (estradiol and progesterone) stimulate the synthesis of vascular endothelial growth factor (VEGF-A), the main modulator of angiogenesis during peri-implantation period. The aim of this work was to study the effect of hypothyroidism on the degree of vascularization and proliferation 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). On day seven of gestation PCNA expression and uterine vascularization were evaluated by immunofluorescence and PCNA and VEGF-A by western blot. Our results demonstrate that hypothyroidism decreases vascularization of the uterine tissue and proliferation (PCNA) of the endothelial and decidual cells during the process of implantation of the embryo. The decrease in PCNA was corroborated by western blot, as well as a significantly decreased in VEGF expression. In conclusion, hypothyroidism affects the vascularization and proliferation of the endometrium during the implantation process in gestation. The decrease in VEGF-A due to hypothyroidism may be responsable for the alteration in uterine tissue vascularization.