汉防己甲素对先天性膈疝大鼠模型胎仔肺发育不良的影响及意义

目的 探讨产前应用汉防己甲素(TET)对先天性膈疝(CDH)大鼠模型胎仔肺内表面活性蛋白B(SP-B)和增殖细胞核抗原(PCNA)的影响及意义.方法 10只成年雌性SD大鼠配种后,于孕9.5 d随机分为3组:对照组(2只)、膈疝组(4只)和治疗组(4只),膈疝组和治疗组一次性灌胃给予除草醚125 mg/只(溶于2.5ml橄榄油中),对照组灌胃给予等量橄榄油.配种后18.5 d时,治疗组给予30 mg/kg汉防己甲素灌胃(1次/d,连续3 d),膈疝组和对照组给予等量生理盐水.孕21 d对孕鼠行剖宫产,观察胎鼠膈疝形成情况,取出肺组织行HE染色并行图像分析,采用免疫组化染色法检测胎肺内SP-B和PCNA的表达情况.结果膈疝组和治疗组共有48只胎鼠形成膈疝,其致畸率为64.9%,二组之间致畸率差别无统计学意义(P>0.05).膈疝组胎鼠存在肺发育不良,产前给予TET干预,肺组织在形态上有明显改善,外形接近于对照组.正常肺组织中,SP-B在肺泡上皮细胞及远端支气管上皮细胞的胞浆内表达,在膈疝组中未见SP-B表达.治疗组中可见SP-B表达,但低于对照组(P<0.01).PCNA阳性细胞率在对照组与膈疝组的差异无统计学意义(P>0.05),但在治疗组中其表达显著较前二组为低,差异有统计学意义(P<0.01).结论 产前应用TET可诱导CDH胎鼠肺的成熟,促进肺内SP-B表达升高;同时,产前给予TET干预的CDH胎鼠,其肺内PCNA阳性细胞率明显降低,提示TET诱导CDH胎肺的成熟并不是依靠促进细胞增殖来完成的.

The effect of prenatal Tetrandrine treatment on pulmonary hypoplasia in fetal rats with nitrofen-induced congenital diaphragmatic hernia

Objective To investigate the effects of prenatal tetrandrine (TET) treatment on the expression of surfactant protein B (SP-B) and proliferation cell nuclear antigen (PCNA) in lung tis-sues of fetal rats with nitrofen-induced congenital diaphragmatic hernia (CDH). Methods Ten preg-nant female Sprague-Dawley rats were randomly divided into 3 groups: Control group (n = 2),CDH group (n = 4) and TET group (n = 4). The rats of CDH group and TET group were administered with 125 mg nitrofen dissolved in 3.0 ml olive oil by gastric gavage. The same volume of olive oil was given to the rats of Control group. From gestation day 18.5,30 mg TET was administered by gastric gavage to the TET group rats once a day for three days. Same dose of natural saline was given to the rats of Control group and CDH group. On day 21 of gestation,all the fetuses were delivered by cesarean sec-tion. The rat fetuses were sacrificed and examined for diaphragmatic hernia. Lung histological studies were made on H&E staining slides. Immunohistochemical staining was performed to detect SP-B and PCNA in lung tissues. Results Of the 74 fetuses harvested from the rats of CDH and TET groups,CDH was found on 48 fetuses of (64.9%). The incidence of CDH between CDH group and TET group was similar (P>0.05). Hypoplastic lungs were noted on the fetal rats of CDH group. Im-proved lung development was found on TET group fetal rats. On the rats of control group,strong ex-pression of SP-B was found in the alveolar and distal bronchial epithelium,but no SP-B positive cells were found in the lung tissues of CDH group fetal rats. After prenatal TET treatment,moderate ex-pression of SP-B was found in the lung tissues of TET group,and it was significantly lower than that of Control group (P<0.01). There was no differences of the percentage of PCNA positive cells be-tween the Control group and CDH group (P>0.05). Compared with the other 2 groups,PCNA posi-tive cells in TET group were significantlydecreased (P < 0.01). Conclusions Prenatal tetrandrine (TET) treatment can accelerate fetal lung differentiation and maturation,and increase the expres-sion of SP-B in the hypoplastic lungs of the fetal rats with nitrofen-induced CDH. PCNA positive cells were decreased in the lung tissue of TET group rats,which indicates TET may not enhance lung mat-uration in CDH rat fetuses by increasing proliferation.