Microarray gene expression analysis in ovine ductus arteriosus during fetal development and birth transition.

Patent ductus arteriosus (PDA) in the newborn is the most common congenital heart anomaly, and is significantly more common in preterm infants. Contemporary pharmacological treatment is effective in only 70 to 80% of the cases. Moreover, indomethacin or ibuprofen, which are used to close a PDA may be accompanied by serious side effects in premature infants. To explore the novel molecular pathways, which may be involved in the maturation and closure of the ductus arteriosus (DA), we used fetal and neonatal sheep to test the hypothesis that maturational development of DA is associated with significant alterations in specific mRNA expression. We isolated DA and a segment of ascending aorta from preterm (97±0 days gestation) and near-term (136 ± 0.8 days) fetal sheep (full term = 145 days) and from 12±0 hours old newborn lambs (obtained from Pozzi Ranch, Valley Ford, CA)). Four animals (n=4) were used for each experimental group. At the time of experimental study, ewes and newborn lambs were euthanized with an overdose of the proprietary euthanasia solution Euthasol (pentobarbital sodium 100 mg.Kg-1 and phenytoin sodium 10 mg.Kg-1; Virbac, Ft. Worth, TX).

新生儿动脉导管未闭（Patent ductus arteriosus, PDA）是最常见的先天性心脏畸形，在早产儿中发病率显著更高。当前的药物治疗仅对70%至80%的病例有效。此外，用于闭合动脉导管未闭的吲哚美辛或布洛芬可能会对早产儿造成严重不良反应。为探索可能参与动脉导管（ductus arteriosus, DA）成熟与闭合的新型分子通路，我们采用胎羊与新生羊开展实验，以验证如下假说：动脉导管的成熟发育过程与特定mRNA表达的显著改变密切相关。我们分别从妊娠97±0天的早产胎羊、妊娠136±0.8天的近足月胎羊（足月妊娠为145天），以及出生12±0小时的新生羔羊（取自加利福尼亚州福特谷的波齐牧场）体内分离得到动脉导管组织与一段升主动脉。每个实验组均使用4只动物（n=4）。实验研究开展前，通过过量注射专属安乐死溶液Euthasol（成分为戊巴比妥钠100 mg·kg⁻¹与苯妥英钠10 mg·kg⁻¹；Virbac公司，得克萨斯州沃斯堡）对母羊及新生羔羊实施安乐死。