α肾上腺素对重症急性胰腺炎大鼠肺脏水调节能力的研究

Role of Alpha Adrenoceptor on Modulating Water in Lung of Severe Acute Pancreatitis Rat Model

目的探讨α肾上腺素对大鼠重症急性胰腺炎(SAP)模型中肺脏水调节能力的影响。方法 15只SD大鼠随机分为假手术组和SAP组,SAP组根据造模后取材的不同时相分为SAP 4 h组和SAP 24 h两个亚组,每组5只大鼠。测定各组大鼠肺脏的肺水清除率(AFC),然后进一步应用α1肾上腺素抑制剂prazosin和α2肾上腺素抑制剂yohimbine处理SAP组大鼠后再观察AFC的变化。用real-time PCR方法测定α1和α2肾上腺素受体m RNA在各组大鼠肺脏组织中的表达。结果 1各组肺脏湿干比变化:与假手术组比较,SAP组4 h(P<0.05)和24 h(P<0.05)时的肺脏湿干比均明显下降;与SAP组4 h时比较,SAP组24 h时的肺脏湿干比进一步降低(P<0.05)。2 AFC变化:SAP组大鼠肺脏在4 h和24 h时的AFC均明显高于假手术组(P<0.05),但SAP组24 h时较4 h时轻度下降,但差异无统计学意义(P>0.05)。经过α1肾上腺素受体抑制剂prazosin或α2肾上腺素受体抑制剂yohimbine作用后,其AFC较SAP组相应时相均明显下降(P<0.05),但仍明显高于假手术组(P<0.05);经prazosin和yohimbine联合作用后,其AFC较SAP组、SAP+prazosin组和SAP+yohimbine组相应时相均明显下降(P<0.05),几乎完全抑制到假手术组的水平(P>0.05)。3 SAP组4 h和24 h时,大鼠肺脏组织中α1和α2肾上腺素受体m RNA表达水平均明显高于假手术组(P<0.05),但SAP组24 h时较SAP组4 h时仅轻度下降,二者比较差异无统计学意义(P>0.05)。结论本研究初步研究结果提示,α1、α2肾上腺素受体均可能参与了大鼠SAP时肺脏水的调节。

Objective To explore effect of α-adrenoceptor on modulating water of lung in severe acute pancreatitis（SAP） rat. Methods The SD rats were randomly divided into sham operation group（n=5） and SAP group, the SAP group was divided into subgroups of SAP-4 h（n=5） and SAP-24 h（n=5）. SAP model was made by injecting taurocholate into bilopancreatic duct. The wet-to-dry ratio, alveolar fluid clearance（AFC）, and AFC affected by α1-adrenoceptor inhibitor-prazosin and α2-adrenoceptor inhibitor-yohimbine separately or together were measured in the lungs. The α1-adrenoceptor and α2-adrenoceptor m RNA expressions in the lungs tissues were measured by real-time PCR. Results1 The wet-to-dry ratios in the SAP-4 h group and SAP-24 h group were obviously decreased as compared with the sham operation group（P〈0.05）, which in the SAP-24 h group was significantly lower than that in the SAP-4 h group（P〈0.05）. 2 The AFCs in the SAP-4 h group and SAP-24 h group were obviously increased as compared with the sham operation group（P〈0.05）. The AFCs in the SAP with α1-adrenoceptor inhibitor-prazosin or α2-adrenocpetor inhibitor-yohimbine or prazosin combined with yohimbine were all obviously decreased as compared with the SAP group（P〈0.05）. 3 The α1 adrenoceptor and α2 adrenoceptor m RNAs in the SAP-4 h group and SAP-24 h group were obviously increased as compared with the sham operation group（P〈0.05）. Conclusion AFC might be modulated by α-adrenoceptor in SAP rat.