Effect of three extracts of Fufang Dihuang decoction on relaxation of mesentery artery in streptozotocin -induced diabetic rats / 中国临床药理学与治疗学

ABSTRACT

AIM: To investigate the effects of three extracts of Fufang Dihuang decoction on the relaxation of mesentery artery in streptozotocin(STZ)-induced diabetic rats. METHODS: Diabetic rat model was induced by i.p injection STZ at a dosage of 60 mg?kg~ -1 . 30 d later, 95% ethanol, 70% ethanol or water extract of Radix Rehmanniae was p.o administrated for 30 d at the dosage of 107.8 , 154.7 and 56.8 mg?kg~ -1 , respectively. On the 60th day, the responses of mesentery artery were determined in the absence or presence of L-argine (L-Arg), N-Nitro-L-argine (NLA) and Indomethacin (Ind). RESULTS: The relaxation of mesentery artery of diabetic rat was diminished compared with the normal control. The basal release of NO and the L-argine-induced release of NO decreased 64.6 %, 77.6 % respectively in diabetic group compared with the normal control, with the decreased proportion of NO in the endothelium dependent relaxation. 95% and 70% ethanol extract of Fufang Dihuang decoction ameliorated the impaired release of NO in rat's mesentery artery. CONCLUSION: Abnormal relaxation of mesentery artery in diabetic rat may be due to the decreased releasing of NO. The extracts of Fufang Dihuang decoction can protect the endothelium cells and improve the relaxation of mesentery artery, among them 70% ethanol extract exert the best potency, followed by 95% ethanol extract. And the water extract has a poor effect.