Alloxan-induced diabetes in the rat - protective action of (-) epicatechin?

Administration of alloxan (150 mg/kg body weight, i.p.) to male Wistar rats induced a reproducible and persistent diabetes mellitus as evidenced by elevated serum glucose and low serum insulin concentrations. Administration of either (-)epicatechin or (+)catechin (250 mg/kg, i.p. on each occasion) at 36, 24, 12 and 1 hour before and at 12 and 24 hours after alloxan administration did not prevent the induction of the diabetes. Similarly, treatment of animals with (-)epicatechin or (+)catechin (125 mg/kg i.p. twice daily) for 21 days commencing 24 hours after alloxan administration did not reverse the persisting elevated serum glucose and low serum insulin concentrations. Moreover, administration of these compounds did not relieve any of the symptoms of the alloxan-induced diabetes such as poor weight gain, polyuria or polydipsia. Thus, this study does not confirm previous reports of prophylactic and curative effects of (-)epicatechin against alloxan-induced diabetes in rats, in spite of the high dosages of the compounds used in these experiments.