原钒酸钠对小肠糖吸收的影响

目的　观察原钒酸钠对葡萄糖及麦芽糖吸收的影响 ,并初步探讨其影响糖吸收的机制。方法　①正常Wistar大鼠分为正常对照组、生理盐水对照组、阿卡波糖组 (30mg·kg-1)、原钒酸钠大剂量 (16mg·kg-1)、中剂量 (4mg·kg-1)和小剂量 (1mg·kg-1)组 ,分别灌胃葡萄糖和麦芽糖后 ,用氧化酶法测空腹血糖值及糖耐量。②从小肠上段提取α 葡萄糖苷酶 ,检测原钒酸钠对酶的抑制作用。结果　①原钒酸钠可延迟灌胃葡萄糖 (2 2g·kg-1)引起的血糖升高且 3个剂量组血糖曲线下面积 (AUC)均低于对照组 ,分别为 (8 2 4±0 6 3)mmol·h-1·L-1(P <0 0 1) ,(9 6 9± 0 38)mmol·h-1·L-1(P <0 0 1) ,(13 76± 0 39)mmol·h-1·L-1(P <0 0 5 ) ;②原钒酸钠和阳性对照组均可延缓灌胃麦芽糖 (2 2g·kg-1)引起的血糖升高 ,且大、中剂量可抑制血糖峰值升高 (P <0 0 5 ) ,各给药组AUC均低于对照组 ,大剂量和中剂量为(8 97± 1 5 6 )和 (6 19± 0 4 7)mmol·h-1·L-1均低于阳性对照组 (13 10± 0 4 3)mmol·h-1·L-1(P <0 0 5 ) ;③原钒酸钠 1、10、10 0 μmol·L-1均可抑制正常大鼠小肠α 葡萄糖苷酶的活性 ,其抑制百分率分别为 5 9 76 %、6 8 18%、87 2 2 % ,且大剂量和中剂量均大于阳性对照组的 6 0 94 % ,分别为P<0

The effect of sodium orthovanadate on sugar absorption of small intestine in rats

AIM To observe the effect of sodium orthovanadate on glucose and maltose absorption and to reveal its mechanism. METHODS ① Normal Wistar rats were divided into 6 groups at random, 0 9% NaCl group, acarbose group(30 mg·kg -1 ) and sodium orthovanadate high dose(16 mg·kg -1 ), middle dose (4 mg·kg -1 ) and low dose (1 mg·kg -1 )groups. The values of blood glucose of all the groups were measured with oxidation enzyme method after administration of glucose and maltose. ② The α glucosidase was abstracted from the upper small intestine and the inhibitory effect of sodium orthovanadate on α glucosidase was examined. RESULTS ① Sodium orthovanadate could delay the peak values of plasma glucose induced by glucose, with AUC in these groups lower than that in controls, that is (8 42±0 63) mmol·h -1 ·L -1 ( P <0 01),(9 69±0 38) mmol·h -1 ·L -1 ( P <0 01) and (13 76±0 39) mmol·h -1 ·L -1 ( P <0 05). ② Sodium orthovanadate and acarbose groups could delay the peak values of plasma glucose induced by maltose and high and middle dosage could suppress the increasing values of plasma glucose. Besides, AUC in all drug administrated groups were lower than normal controls, that is (8 97±1 56) mmol·h -1 ·L -1 ( P <0 01) in high dosage group and (6 19±0 47) mmol·h -1 ·L -1 ( P <0 01) in middle dosage group. ③ Sodium orthovanadate could suppress the activity of α glucosidase in intestine of normal rats with three dosage 1,10 and 100 μmol·L -1 , and the percentages of inhibition were 59 76%, 68 18% and 87 22%, respectively. CONCLUSION Sodium orthovanadate can reduce and delay the absorption of maltose and glucose. The mechanism may be that it can inhibit the activity of α glucosidase except for its inhibition of Na +,K + ATP ase in small intestine.