Ineffectiveness of cholic acid and cyprinol sulfate on the toxicity of streptozotocin in rats

The possible effects of bile acid and bile alcohol on the visual acuity of streptozotocin (STZ)-induced hyperglycemia male Wistar rats were investigated. Forty-eight rats were divided into two groups, STZ and non-STZ, and intraperitoneally injected with STZ (60 mg/kg body weight in 0.6 mL of saline) and saline (0.6 mL) on day 1, respectively. After 4 days of STZ treatment, all the rats were tested for glycosuria and then divided into four groups. Each group had 6 rats and the rats were treated orally every 3 days with saline and the non-toxic dosages of cholic acid (37 mg/kg) and cholic acid (74 mg/kg) combined with cyprinol sulfate (37 mg/kg). At the end of the 29-day experiment, the results revealed that the relative ratios of liver and kidney weight to body weight, the concentrations of RBC, hemoglobin and hematocrit in the blood, as well as the levels of AST, ALT, ALP, BUN and creatinine in the plasma of the rats were not significantly different. However, the levels of plasma glucose and liver thiobarbituric acid-relative substances (TBARS) in the rats treated with STZ were higher, while the levels of vitamin A in the comea were contrarily lower than those of the non-STZ rats. The values of three indicators (plasma glucose, liver TBARS and vitamin A) related to visual acuity were not significantly influenced when the rats were treated with cholic acid alone or combined with cyprinol sulfate in the STZ or non-STZ group. The results indicated that both cholic acid and cyprinol sulfate could not influence the toxicity of STZ in rats.