Effect of Long Term Administration of Copper Pyrazinate on Copper Levels in Serum, Liver and Muscle with Reference to Some, Haematological and Biochemical Constituents in Rats

Abstract: This study was carried out to investigate the effect of long term oral administration of copper pyrazinate at doses of 0.8 and 4.0 mg/kg b.wt. for 10 weeks in rats on copper level in serum, liver and muscle with reference on some haematological and biochemical constituents. LD 50 of copper pyrazinate in mice was also determined. Results revealed that copper serum level was increased (P<0.05) in a dose and duration dependent manner. Copper concentrations in liver and muscle tissue of treated rats was increased (P<0.05) transiently within the first two weeks, however, its level returned to that in control rats 6 weeks after. The total leukocytes, erythrocytes and platelets counts and haemoglobin concentration were decreased after oral administration of copper pyrazinate in a dose of 0.8 or 4.0 mg/kg b.wt. compared to the control group. Eosinopenia was also recorded. Liver enzymes activity was not significantly changed except alanine aminotransfererase (ALT) which was increased when copper pyrazinate was given in a dose of 4.0 mg/kg for 8 weeks. Serum urea and creatinine showed no significant changes. However, cholesterol level was increased in serum of rats treated with the larger dose of copper pyrazinate for 8 weeks. The safety of copper pyrazinate was also confirmed by the high LD 50 in mice (750.0 and 118.33 mg/kg b.wt. after oral and i.p. administration, respectively). In conclusion, administration of copper pyrazinate to rats at doses of 0.8 or 4.0 mg/kg b.wt. revealed very mild changes in liver function, haemogram and copper levels in liver and muscle.