Histological And Histochemical Studies On The Decidua And The Uterine Glands During Early Pregnancy In The Rat (Rattus rattus)

Abstract

Histological and histochemical studies were carried out on the decidua and uterine glands in the uteri of pregnant rats 'Rattusrattus' between 129 hours post.-coitum (p.c) and day nine of pregnancy. Decidualization was increased from 129 h p.c. to 153 p.c. and reached its maximum at day nine of pregnancy. The decidual cells showed a dense basophilic cytoplasm and large nuclei. Each nucleus contained one to five deeply stained nucleoli. Cells of the decidua appeared rich in proteins, RNA-containing particles and polysaccharides. These biological materials were present in considerable amounts in the intercellular spaces and very near to the implantation chamber. The uterine glands were few in number and located away from the implantation chamber. Cells of the uterine glands contained moderate to large amount of proteins, RNA -containing particles and a small to moderate amount of polysaccharides. In most of the specimens examined, the lumina of the uterine glands did not display any secretory material. These observations led to the assumption that the decidua, and not the uterine glands, play an important role in the nutrition of the developing rat embryo before placentation is completed.