Indian Journal of Science and Technology

Abstract

Objectives: This study was carried out to identify the histomorphological and histochemical aspects of the uterus in the adult guinea pig (Cavica porcellus). To conduct such project, fourteen adult guinea pigs at their diestrous period were bought from the local breeders directly. Methods: Animals were euthanized, dissected, and subsequently uteruses specimens were collected and fixed by 10% neutral buffered formalin and some specimens were fixed in Bouin’s solution for subsequent histochemical staining. Then after specimens were subjected to routine processes such as dehydration, clearing, embedding, and block preparation. Sections of 6 µm were prepared and stained with haematoxylin–eosin, Masson’s Trichrome, Alcian blue (pH 2.5), and Periodic acid shiff stains. Findings: Gross findings of the uteruses revealed duplex uterus in the guinea pigs. It possessed two separate uterine horns united caudally to form the body, suspended by mesometrium in the abdominal cavity. Caudally, body formed the cervix, which was short and projected into the vaginal cavity forming portio vaginalis uteri with one cervical orifice.Microscopic findings revealed abrupt changes in the wall of the isthmus into the uterine horn at the utero-tubal junction. The wall of the uterus showed endometrium, vascular layer, myometrium, and adventitia or serosa. Lining epithelium was simple columnar which was similarly lined the endometrial glands. Myometrium was consisted of inner circular and outer longitudinal bundles of smooth muscle fibers. In the body, the lining epithelium was replaced gradually by simple mucous columnar epithelium. In addition to that the mucosa was thrown into long folds leaving small lumen at the cervix called os cervix. Such changes were associated with endometrial glands gradual diminishing till the cervix. Histochemically, the non-ciliated columnar cells present in the body and cervix were stained positively with AB (pH 2.5) and PAS stains. The reaction with AB (pH 2.5) was more intense compared with the staining with PAS so that it indicated that mucin was more acidic than neutral in nature.
Keywords: Guinea Pig, Uterus, Diestrous, Histochemistry