Ameliorative Effect Of Ginkgo Biloba Extract On Gamma Radiation Injury: Histological And Histochemical Evaluation In Rats

Abstract

The present study aimed to evaluate the impact of exposure to ionizing radiation and the effect of preexposure treatment with extract of Ginkgo Biloba (EGB) on hepatic tissue architecture and hepatocyte cytoplasmic organelles and DNA. The study comprised of 30 Wistar-Albino rats (2.5 month old) separated into 3 equal groups (n=10). Group I: received EGB at a daily dose of 50-mg/kg by intraperitoneal injection for 8 weeks. Group II: received whole-body Gamma irradiation performed by a Cesium-137 ventilated Gamma Cell-40 at a dose rate 1 Gy/1.5 min.- once a week for 8 weeks and Group III: received EGB at a daily dose of 50-mg/kg by intraperitoneal injection for 2 weeks before and for 8 weeks during irradiation in a dose similar to Group II. Liver section in groupI showed polyhedral hepatocytes with no or mildly vacuolated cytoplasm, containing basophilic granules and central rounded vesicular nuclei and showed moderate PAS+ve reaction. Some hepatocytes contained more glycogen content than the others, by using Pritchard’s technique and fat droplets appeared black in color by using Sudan black stain. Hepatocytes were studded with mitochondria, significant increase in DNA content with evident mitotic figures in some cells by using Feulgen reaction. In Group II, liver section showed that most of the hepatocytes were compacted and vacuolated with pyknotic nuclei and large area of cellular infiltration with significant decrease of the +ve PAS reaction and most of the hepatocytes lacked their glycogen content than the others with marked decrease in the fat content (Sudan black stain). Also liver section showed marked decrease in the mitochondrial content (Pritchard’s technique) and marked decrease in the DNA content shown as faintly stained nuclei (Feulgen reaction). Most of the hepatocytes in Group III liver were in mitotic state, stages of division, polyploidy could be observed and the cytoplasm became condensed and granulated with significant increase of +ve PAS reaction and near normal black-stained fat droplets (Sudan black stain). By using Pritchard’s technique, the liver of Group III showed apparent increase in the