银杏叶提取物对糖尿病大鼠血管功能的影响

目的:探讨银杏叶提取物对高糖高脂诱导的Ⅱ型糖尿病大鼠血管张力变化的影响及可能的机制.方法:将大鼠随机分为正常对照组(Control)、糖尿病组(DM)、银杏叶提取物高剂量(H)及低剂量(L)组,灌胃5周后检测血清中晚期糖化终产物(AGEs)、血脂的含量和肠系膜上动脉张力变化.结果:H组甘油三酯、胆固醇、AGEs含量明显比DM组降低,高钾激动下,DM组血管的维持相下降明显;去内皮血管苯肾上腺素(PE)激动引起的收缩PD2DM组减少,血管顺应性有下降的趋势.尽管L组变化不明显,但H组对高钾(下降率:22.52±5.48%vs DM:44.19±11.03%,P＜0.05)、PE(PD2:6.15±0.22vsDM:6.62±0.13,P＜0.05)激动的反应明显优于DM组,血管功能学改善明显.结论:银杏叶提取物能降低糖尿病大鼠血清甘油三酯、胆固醇、AGEs含量,减少自由基对血管的损伤,从而改善血管功能病变.

Study on the Effect of Ginkgo biloba Extract on the Tension of Diabetic Rat Artery

OBJECTIVE: To investigate the effect and possible mechanism of Ginkgo biloba extract EGB50 on vascular tension of type II diabetes mellitus (DM) induced by hyperglycemia and hyperlipidemia. METHODS: Rats were randomly divided into normal control rats (Control), diabetic rats (DM), diabetic rats oral-treated with higher dose Ginkgo biloba extract EGB50 (H) and diabetic rats treated with lower dose EGB50 (L). The serum levels of Advanced Glycosylation end-products (AGEs), cholesterol (CHOL), triglyceride (TRIG) and superior mesenteric artery tension were quantified and measured. RESULTS: After 5 weeks' oral-treatment, serum CHOL, TRIG and AGEs increased, sustained phase of contractile response in high K+ solution and PD2 of phenylephine decreased in diabetic arteries. The biochemical indexes and the tension of vascular function had less significance in L group, but improved distinctly in EGB50 H group (decreasing rate in high K+ solution: 22.52 +/- 5.48%, vs DM:44. 19 +/- 11.03%, P < 0.05) (PD2 of PE: 6.15 +/- 0.22 vs DM: 6.62 +/- 0.13, P < 0.05). CONCLUSION: EGB50 is capable of reducing serum hyperlipidemia,the concentration of AGEs, thus it can reduce the impairment of the oxidants to endothelium cells of vessels and improve pathological and functional change of artery of diabetes.