【摘要】 目的:观察左心室内推注藜芦定诱发的Bezold-Jarisch反射(BJR),并建立犬BJR模型。方法:7只杂种犬麻醉后经左颈动脉插入心导管至左心室,先后经心导管弹丸式推注藜芦定5、10、15和20μg/kg,记录心率(HR)、平均动脉压(MAP)推药前的基础值、推药后的最低值及最大下降值ΔHR、ΔMAP。待前一剂量藜芦定推注后HR及MAP恢复至推药前的基础值水平并稳定15min以上后再推注后一剂量。观察藜芦定剂量与ΔHR、ΔMAP所占基础值百分比之间的关系,以两者百分比均>50%作为犬BJR模型的标准。结果:7只犬左心室内推注4个不同剂量藜芦定后均诱发出BJR,表现为HR及MAP的一过性下降,两者的最低值均明显低于基础值(P<0.01)。推药后HR的最低值随推药剂量增大而减少,ΔHR百分比随推药剂量增大而增大,相邻2个剂量之间的HR最低值及ΔHR百分比相比,差异均有统计学意义(P<0.05)。推药后MAP的最低值随推药剂量增大而减小,但相邻2个剂量之间的MAP最低值相比,仅10与5μg/kg之间差异有统计学意义(P<0.05);ΔMAP百分比随推药剂量增大而增大,10与5μg/kg之间、15与10μg/kg之间ΔMAP百分比相比差异均有统计学意义(P<0.05)。15和20μg/kg藜芦定推注后ΔHR及ΔMAP百分比平均值均>50%。结论:左心室内弹丸式推注15和20μg/kg藜芦定能成功建立犬BJR模型,该方法操作简便、可靠性高。更多还原

【Abstract】 Objective: To observe the Bezold-Jarisch reflex(BJR) induced by veratridine injected into the left ventricle,and to construct a Bezold-Jarisch reflex model in dogs.Methods: Seven mongrel dogs were injected with veratridine at bolus doses of 5μg/kg,10μg/kg,15μg/kg and 20μg/kg through a cardiac catheter inserted from the left carotid artery into the left ventricle to induce BJR.Changes of heart rate(HR)and mean arterial pressure(MAP) were observed;their minimum values and the maximum decrements,indicated with ΔHR and ΔMAP,were measured and compared with their baseline values.A second dose followed when HR and MAP returned to the baseline and stayed there for over 15 minutes.The relationship between the doses of veratridine and the percentages of ΔHR and ΔMAP was analyzed.The standard for the canine BJR model was that the rates of ΔHR and ΔMAP were > 50%.Results: BJR was induced by injecting 4 different doses of veratridine into the left ventricle of the dogs,which was shown by a decrease of HR and MAP,with their minimum values significantly lower than the baseline(P< 0.01).The minimum value of HR decreased while the percentage of ΔHR increased with the increased dose of veratridine,with statistically significant differences between the minimum values of HR as well as between the percentages of ΔHR induced by adjacent doses(P< 0.05).The dose of veratridine was negatively correlated with the minimum value of MAP,with significant differences only between the does of 10 and 5μg/kg(P< 0.05) when the minimum values of MAP induced by adjacent doses came into comparison,but positively correlated with the percentage of ΔMAP,with significant differences between the doses of 10 and 5μg/kg as well as between 15 and 10μg/kg(P< 0.05).The rates of ΔHR and ΔMAP both exceeded 50% after veratridine injection at the doses of 15 and 20μg/kg.Conclusion: The dog model of BJR can be successfully established by injecting veratridine at the bolus doses of 15 and 20μg/kg into the left ventricle,and the method is easy and highly reliable.更多还原