In vivo studies on evaluation of potential toxicity of unspent tannins using albino rats (Rattus norvegicus)

The present study emphasizes the effect of unspent tannins on liver, kidney and heart of albino rats. Oral administration of unspent tannins at three different concentrations was made for a period of seven days. Carbon tetrachloride served as positive control. Tissues were removed carefully followed by sacrifice and were subjected to sectioning and H&E staining. Histopathological examination of the sections showed, major tissue damage with the highest concentration of tannins (1500 mg/kg body weight) irrespective of their nature and source, followed by moderate damage with the 1000 mg/kg bw and zero damage with 500 mg/kg bw. However, complete damage was observed with the tissues of positive control group. Lipid peroxidase assay using post-mitochondrial supernatant of liver, kidney and heart showed appreciable levels of malondialdehyde release at higher concentrations of tannins.