颈交感神经干离断对妊高征大鼠胎盘NO含量及NOS基因表达的影响

Influence of transection of the cervical sympathetic trunk on content of NO and expression of NOS in placenta of rats with pregnancy-induced hypertension syndrome

目的:观察颈交感神经干离断(TCST)对妊高征(PIH)大鼠胎盘一氧化氮(NO)含量及内皮型一氧化氮合酶(eNOS)和诱导型一氧化氮合酶(iNOS)基因表达的影响。方法:妊娠大鼠随机分5组,每组15只。对照组(C):自妊娠14d开始皮下注射生理盐水至孕20d;妊高征1组、2组(H1、H2):自妊娠14d开始皮下注射L-NAME分别为125mg.kg-1.d-1和62.5mg.kg-1.d-1,至孕20d;手术组(O):妊娠第14d行右TCST,余同B1;假手术组(S):妊娠第14d行右颈交感神经干分离,但不离断,余同H1。孕21d剖宫取仔。观察孕鼠血压、尿蛋白,胎鼠的大小、体重、畸形率、死亡率,胎盘NO含量、eNOSmRNA、iNOSmRNA表达。结果:(1)血压、尿蛋白除基础值外H1、H2组各时点值明显高于C组(P<0.01);H2组明显低于H1组(P<0.01);O组与C组相比差异无显著(P>0.05)。(2)胎鼠体重、大小H1、H2组明显低于C组(P<0.01);H1组明显低于H2组(P<0.05,P<0.01);O组与C组相比差异无显著(P>0.05)。死亡率、畸形率变化与上述指标相反。(3)胎盘NO含量及eNOSmRNA、iNOSmR-NA表达H1、H2组明显低于C组(P<0.01);H1组明显低于H2组(P<0.01,P<0.05);O组明显高于H1组(P<0.01),且与C组比无显著差异(P>0.05)。结论:TCST可保护孕鼠免受妊高征的影响,可能与其具有改善孕鼠胎盘组织eNOSmRNA、iNOSmRNA表达和NO含量有关。

AIM： To observe the influence of transection of the cervical sympathetic track （TCST） on the content of NO and the expression of eNOS mRNA and iNOS mRNA in placenta of the rats with pregnancy - induced hypertension syndrome （PIH）. METHODS： Pregnant Wistar rats were randomly divided into 5 groups： control group （C） ： saline was injected subcutaneously from 14th day to 20th day of gestation; PIH group 1 （HI） and group 2 （H2）： L- NAME was respectively injected with 125 mg/kg and 62. 5 mg/kg, respectively, then the other procedures were the same as group C; Operation group （O） ： TCST was operated on 14th day of the gestation, then the other procedures were the same as group H1 ; sham operation group （S） ： the cervical sympathetic trunk was only separated and exposed on 14th day of the gestation, then the other procedures were the same as group HI. RESULTS ： （ 1 ） Except the base value of the BP and protein in urine of the pregnant rats, all the parameters observed in group H1 and H2 were higher than those in group C significantly （P 〈 0. 01 ）, and in group H2 were lower than those in group B1 markedly （P 〈0. 01 ）. （2） In comparison with those in group C, the size and body weigh of fetus in group H1 , H2 decreased markedly （P 〈0.01 ）. The above indexes in group H1 were lower than those in group H2 markedly （ P 〈 0. 01, P 〈 0. 05 ）. The changes of the rate of embryo absorption and fetal death, and deformity rate of the fetal rats were contrary to the above indexes. （3） The content of NO and the expression of eNOS mRNA and iNOS mRNA in placenta in group H1 and H2 were lower than those in group C markedly （P 〈0. 01 ）. Those ingroup H1 Were lower than those in group H2 obviously （ P 〈 0.01, P 〈 0. 05 ）. Those in group O were higher than those in group H1 markedly （P 〈0. 01 ）. CONCLUSION： TCST protects pregnant rats against PIH, and it was related to the mR- NA expression of eNOS and iNOS and the content of NO in placenta tissue .