Involevements of A- and B-adrenergic receptors in the pyrethroids-induced hyperglycemia in rats

ABSTRACT

The effects of permethrin and cypermethrin on blood glucose levels, the serum insulin level and on liver glycogen content were assessed in rats. Intraperitoneal administration of cypermethrin in two dose levels [100, 200 mg/kg] caused about 2-3 fold increase of blood glucose concentration. Administration of permethrin in a low dose level [250 mg/kg] failed to produce significant changes of blood glucose concentration. Yet, in a high dose level [500 mg/kg], it increased the blood glucose concentration by about 50% of the control. The rise in blood glucose level produced by cypermethrin was greater than that produced by permethrin. Cypermethrin or permethrin significantly decreased liver glycogen content, but failed to alter serum insulin level. Simultaneous administration of either prazosin or propranolol with cypermethrin or permethrin counteracted the pyrethroids-induced hyperglycemia. These data suggested that the hyperglycemia produced by cypermethrin or permethrin is mediated by increased hepatic glycogenolysis with involvement of alpha-1 and B- adrenergic receptors