改良心导管测定大鼠肺血管阻力的方法

目的 建立一种简单、可重复性强的测定正常及肺动脉高压大鼠肺血管阻力的方法.方法 雄性Sprague-Dawley( 180 ～ 200 g)大鼠45只,随机分为3组:正常对照组、低剂量野百合碱组(50 mg/kg)和高剂量野百合碱组(60 mg/kg).给予大鼠颈背部皮下一次性注射野百合碱建立肺动脉高压大鼠模型.大鼠肺动脉压力采用自制改良的末端呈圆弧形的PE- 50导管行右心导管法测定.心输出量利用热稀释法原理检测.肺血管阻力由平均肺动脉压力除心输出量得出.结果 三组大鼠肺动脉压力、心输出量及肺血管阻力的检测总成功率均分别为98％、100％和96％,组间差异无统计学意义.注射野百合碱21 d后,低、高剂量野百合碱组大鼠的平均肺动脉压均显著高于对照组(43.1±0.8)mm Hg(1 mm Hg=0.133 kPa)、(54.8±2.2) mm Hg比(17.4±1.0) mm Hg,P均＜0.001],且高剂量组明显高于低剂量组(P＜0.001).低、高剂量野百合碱组大鼠心输出量均明显低于对照组(77.5±6.9) ml/min、(71.0+6.7)ml/min比(126.8±3.9) ml/min,P均＜0.001],低、高剂量组间差异无统计学意义.低、高剂量野百合碱组大鼠肺血管阻力均显著高于对照组(0.56±0.06) mm Hg·min-1·ml-1、(0.76±0.08)mm Hg·min-1·ml-1比(0.13±0.01)mm Hg- min-1·ml-1,P均＜0.001],且高剂量组明显高于低剂量组(P=0.01).结论 采用此方法检测大鼠肺血管阻力准确、可靠、操作性强,具有推广价值.

Determination of pulmonary vascular resistance by improved right heart catheter in rat

Objective To establish an easy and repeatable method for determination of pulmonary vascular resistance in normal and pulmonary arterial hypertension (PAH) rats.Methods Forty-five Sprague-Dawley rats were randomly assigned into three groups:control group,low dose monocrotaline (MCT) group (50 mg/kg) and high dose MCT group (60 mg/kg).Rats in PAH groups received single subcutaneous injection of MCT.We measured pulmonary artery pressure by right heart catheterization using an improved hand-made PE-50 catheter.Cardiac output was calculated through thermodilution method.Pulmonary vascular resistance equals the mean pulmonary artery pressure divided by cardiac output.Results The total percentages of success to detect pulmonary artery pressure,cardiac output and pulmonary vascular resistance were 98％,100％ and 96％ respectively in 3 groups.Twenty-one days after MCT injection,mean pulmonary artery pressure significantly increased in MCT group compared to control group (43.1 + 0.8 ),(54.8 +2.2) vs.(17.4 + 1.0) mm Hg( 1 mm Hg =0.133 kPa),P ＜0.001 ],and the mPAP was also significantly higher in high dose MCT group than in low dose MCT group (P ＜ 0.001 ).Cardiac output was significantly lower in PAH rats than in control rats (77.5 ±6.9),(71.0 ±6.7) vs.(126.8 ±3.9) ml/min,P ＜0.001 ].Pulmonary vascular resistance was significantly increased in PAH rats compared with control rats (0.56 +0.06),(0.76+0.08) vs.(0.13 ±:0.01) mm Hg · min-1 · ml-1,P＜0.001].There were significant differences in both MCT-treated groups (P =0.01 ).Conclusions Pulmonary vascular resistance in rats could be reliably detected using the improved hand-made PE-50 right heart catheter.