山楂水提取物对猪离体冠状动脉环的舒张作用研究

目的:研究山楂水提取物对猪离体冠状动脉环的舒张作用。方法:观察0.1、0.3、0.5mg·mL-1山楂水提取物对KC(l30mmol·L-1)诱发的猪离体冠状动脉环收缩的舒张作用。以Na+/Ca2+交换体阻滞剂KB-R7943(1×10-6mol·L-1)、电压依赖性钾通道(KV)阻滞剂四胺基吡啶(4-AP,1×10-3mol·L-1)、K+-ATP通道阻滞剂格列苯脲(Gli,1×10-5mol·L-1)、K+/Ca2+通道阻滞剂乙胺(TEA,1×10-2mol·L-1)、内向整流钾通道(KiR)阻滞剂氯化钡(BaCl2,1×10-3mol·L-1)预处理血管环,观察其对山楂水提取物舒血管作用的影响。结果:山楂水提取物对KCl预收缩的猪离体冠状动脉环产生浓度依赖性的舒张作用。用KB-R7943、4-AP、Gli预处理的血管环对山楂水提取物的舒张反应与未经处理时比较无显著性差异(P>0.05)。TEA和BaCl2预处理的血管环对山楂水提取物的舒张反应与未经处理时比较有显著性差异(P<0.01)。结论:山楂水提取物对KCl预收缩的猪离体冠状动脉环具有浓度依赖性的舒张作用,其舒张反应可能与K+/Ca2+通道和KiR通道有关,与Na+/Ca2+交换体、KV通道和K+-ATP通道无关。

Vasodilative Acts of Water Extract from Crategi Fructus on Isolated Porcine Coronary Artery Rings

OBJECTIVE: To investigate the vasodilative acts of water extract from Crategi Fructus on isolated porcine coronary artery rings. METHODS: The effect of water extract from Crategi Fructus 0.1, 0.3 and 0.5 mg·mL-1 on the tensions of the isolated porcine coronary artery ring induced by potassium chloride (KCl,30 mmol·L-1) was observed. Coronary artery rings were treated with Na+/Ca2+ exchanger blocker KB-R7943(1×10-6 mol·L-1), KV channel blocker 4-AP(1×10-3 mol·L-1), K+-ATP channel blocker Gli (1×10-5 mol·L-1), K+/Ca2+ channel blocker TEA (1×10-2 mol·L-1) and KiR channel blocker BaCl2(1×10-3 mol·L-1) in advance. The influence of them on vasodilative acts of water extract from Crategi Fructus was observed. RESULTS: Water extract from Crategi Fructus caused vasorelaxation of porcine coronary artery rings precontracted with KCl (30 mmol·L-1) in a concentration-dependent manner. There was no significant difference in vasorelaxation response of coronary artery rings pretreated with KB-R7943, 4-AP and Gli and those without pretreatment to water extract from Crategi Fructus(P>0.05). There was significant difference in vasorelaxation response of coronary artery rings pretreated with TEA and BaCl2 and those without pretreatment to water extract from Crategi Fructus(P<0.05). CONCLUSION: Water extract from Crategi Fructus could produce vasodilatation effect on KCl pre-contracted porcine coronary artery rings in concentration-dependant manner. The relaxation of the porcine coronary artery rings may be not associated with Na+/Ca2+ exchanger, KV channel and K+-ATP channel but K+/Ca2+ and KiR channel