Preliminary Studies on the Toxic Effects of Degradation Products of Oxytetracycline and Chlortetracycline on Rats

The paper aimed to study the toxic effects of the degradation products of oxytetracycline and chlortetracycline, such as, α-apo-oxytetracycline (α-apo-OTC), β-apo-oxytetracycline (β-apo-OTC), anhydro-chlortetracycline (ACTC) and 4epi-anhydro-chlortetracycline (EACTC) on rats. Male rats received oral doses of 10 mg/kg body weight/day of either α-apo-OTC, β-apo-OTC, ACTC or EACTC for 90 d. At the end of 90 d treatment, the body/organ weight, white blood cell count (WBC), red blood cell count (RBC), hemoglobin (HGB), hematocrit (HCT), platelet (PLT) count, blood urea nitrogen (BUN), serum glutamic oxaloacetic transaminase (SGOT) and serum glutamic pyruvic transaminase (SGPT) were measured. The results revealed that the rats treated with α-apo-OTC or ACTC for 90 d did not affect body, organ weights or certain bloodand serum-factors, however, those treated with β-apo-OTC or EACTC exhibited significant decreases in body weights, RBC counts and HGB concentrations, as well as significant increases in BUN concentrations, SGOT and SGPT activities. The results of this study suggested that the toxic effects of β-apo-OTC or EACTC treatment could damage liver and kidney tissues of rats, as well as lead to the degeneration and necrosis in the hepatocytes.