Effect of Human Growth Hormone to Antioxidant Enzymes in Rat Erythrocyte

Shin, Cheol Wha; Kim, Soo Ah; Jung, Hyuk

Abstract

OBJECTIVES
To observe whether any relationship exists between the dosage of growth hormone and the plasma concentration of malondialdehyde (MDA) or whether a relationship exists between the dosage of growth hormone and the activity of erythrocyte enzymes, superoxide dismutase (SOD) and catalase, on hypophysectomized male rats.
METHODS
We used 40 hypophysectomized Sprague-Dewley rats randomly assigned to four groups. The first group (group A) was allowed to evolve freely with no growth hormone supply. Human growth hormone was administered subcutaneously to the other three groups at dose of 1 IU/kg/day (group B), 4 IU/kg/day (group C) and 8 IU/kg/day (group D) after 2 weeks of recovery date from operation and 4 weeks of growth hormone treatment, blood samples were obtained from the four groups. The concentrations of MDA, the concentrations of erythrocyte catalase and SOD were determined.
RESULTS
There were significant correlations between the dose of growth hormone and the concentrations of erythrocyte catalase and SOD in the group C,D Whereas catalase and SOD activities in erythrocyte was decreased in growth hormone group. Any relationship wasn't found between the growth hormone and plasma MDA levels in all groups.
CONCLUSION
These results suggested that the catalase and SOD in erythrocyte is related the dosage of growth hormone. This model may explain the contradictory findings presented by growth hormone with respect to their pro- or antioxidant action. The further study will be needed to evaluate the effect of growth hormone induced plasma lipid peroxidation.