RESUMO
A study was conducted to examine the clinical signs, hematological, biochemical and histopathological changes in vitamin D(3) toxicity at a dose rate 2 mg/kg b.wt. of vitamin D(3) and to assess the protective effect of Aloe vera in vitamin D(3) toxicity. The clinical signs observed were anorexia, progressive weight loss, difficulty in movement and respiration, diarrhea, epistaxis, subnormal body temperature and nervous signs before death. Mortality was observed in treated rats between day 10 and day 19 of treatment. The gross postmortem changes observed were severe emaciation, white chalky deposits on epicardial surface of heart, pin point white deposits on cortical surface of kidneys with pale yellow discoloration and diffused white deposits on serosal surface of stomach and intestine with bloody ingesta in lumen. The hematological changes included non-significant increase in hemoglobin and total leukocyte count and significant increase in relative neutrophil count. The biochemical changes observed were significant increase in plasma concentration of calcium, phosphorus and blood urea nitrogen, whereas a significant decrease in the concentration of albumin and total plasma protein was observed. The histopathological lesions included calcification of various organs, viz., tongue, stomach, intestines, kidney, heart, aorta, larynx, trachea, lungs, spleen, choroid plexus arteries of brain and vas deferens. The Aloe vera juice (2.5% in drinking water) has no protective effect on vitamin D(3) toxicity (2 mg/kg b.wt.).