Abstract
Aqueous extract of Bambusa vulgaris L. leaves at 250 and 500 mg/kg body weight was investigated for toxic effects in pregnant rabbits. Apparently healthy, female rabbits (Dutch) weighing between 1.62 and 1.70 kg as previously used in our abortifacient study were paired overnight with male rabbits in ratio 2:1 and those that became pregnant were completely randomized into three groups (A-C). Group A (the control), received orally 1.85 mL/kg body weight (3 mL) of distilled water thrice daily on days 1-9 of pregnancy while groups B and C were treated orally with the same volume corresponding to 250 and 500 mg/kg body weight of the extract. Clinical signs of toxicity were not observed in all the animals during the study. The extract did not significantly alter (p > .05) the serum follicle stimulating hormone and total protein content of the pregnant rabbits throughout the exposure period whereas, the concentrations of luteinizing hormone, progesterone, albumin, globulin, urea and calcium decreased in the serum of the rabbits. At 250 mg/kg body weight, the extract increased kidney alkaline phosphatase (ALP) activity whereas at 500 mg/kg body weight of the extract, the ALP level was similar to the control group. Liver ALP at all doses, as well as the activity of gamma glutamyl transferase (GGT) at 500 mg/kg body weight was reduced. This reduction was accompanied by an increase in serum ALP and GGT at these doses. At 250 mg/kg, the extract increased kidney GGT. Conversely, at 500 mg/ kg, kidney GGT activity decreased. Liver and serum GGT were not altered by the 250 mg/kg. The extract also increased the serum levels of creatinine, uric acid, sodium, potassium and bicarbonate ions as well as total and conjugated bilirubin. In the hepatocytes of extract-treated animals, there was no evidence of necrosis, inflammation, fibrosis and degenerative changes in the central vein and radiating hepatic cords, while the glomerulus and the tubules of the nephrons also remained intact. The alterations in biochemical parameters by the aqueous extract of B. vulgaris leaves suggests adverse effect on the synthetic, secretory, reabsorptive and excretory functions of liver and kidney of the animals. Therefore, the absence of histopathological lesions in the hepatocytes and nephrons implies that histopathological changes are not a sensitive assay for the assessment of tissue damage by the extract.