RESUMO
Chard [Beta vulgaris L. var. Cicla] administration could improve the activity of antioxidant systems such as gluthatione and has a hypoglycemic and hypolipidemic property. To evaluate the effect of oral administration of chard on the contractile reactivity of isolated aorta in diabetic rats. This experimental study was conducted at the School of Medicine, Shahed University in 2003. Male Wistar rats were divided into control, chard-treated control, diabetic, and chard-treated diabetic groups. For induction of diabetes, streptozotcin [STZ] was intraperitoneally administered [60 mg/Kg]. Chard-treated groups received chard mixed with standard pelleted food at a weight ratio of 1/15. After one month, contractile reactivity of aortic rings to KC1 and noradrenaline was determined using isolated tissue setup. Serum glucose level showed a significant increase [409/4 and 401/3 mg/dl] in diabetic group at 2[nd] and 4[th] weeks [P<0.001], while this increase was less obvious in chard-treated diabetic group [274/5 and 161/2 mg/dl] [P<0.01 and P<0.001 for 2[nd] and 4[th] weeks, respectively]. In addition, the latter group showed a lower contraction to KC1 [P<0.05] and noradrenaline [P<0.01] as compared to diabetic group [0/76 and 1.41 g/mm [2] of the aortic ring]. Meanwhile, there was no significant difference between control and chard-treated control groups regarding contractile reactivity. Oral administration of chard for one month could attenuate the contractile responsiveness of the vascular system and may prevent the development of hypertension in diabetic rats