Histological and immunohistochemical study on the effect of pregnancy and lactation on the jejunal mucosa of albino rat

ABSTRACT

This study was carried out to investigate the effect of pregnancy and lactation on the structure of jejunal mucosa. Fifteen adult female albino rats were used in this study. They were classified into three groups of five animals each. Group I included virgin rats, which act as control. Group II comprised pregnant rats at the third week of pregnancy. Group III consisted of lactating rats at the third week of lactation. All the animals were decapitated and jejunal specimens were taken and processed for histological, immunohistochemical and electron microscopic study. Morphometric study was also done and the obtained results were statistically analyzed. The results of the present study revealed that villus height increased during pregnancy and was maximum at lactation. The surface area of the enterocytes along the villi was significantly increased during pregnancy while their number was significantly increased during lactation. Immunohistochemical staining of proliferating cell nuclear antigen [PCNA] of cells in the crypt region showed a significant decrease in number of PCNA positive cells during pregnancy and a significant increase in their number during lactation. Electron microscopic results showed a significant increase in the microvillus height in lactating rats. Hypertrophy of the mitochondria and proliferation of rER were also evident during pregnancy and lactation. It is concluded that pregnancy and lactation induced morphological changes in the jejunal mucosa. These changes were accompanied by a decrease in cell turn over and a longer residence time of enterocytes during pregnancy