慢性亚致死性缺氧对未成熟脑结构和发育的影响

Chronic sublethal hypoxia： challenge to premature brain in structual and neurological devdopmen

现代新生儿学的发展促使极低体质量早产儿的存活率显著提高，同时严重慢性肺部疾病患儿增多，特别是支气管肺发育不良（BPD）。中重度BPD患儿多数有远期感觉、运动和认知缺陷。有些功能缺陷可能发展至学龄期或成年甚至持续终生。越来越多的临床数据表明BPD显著影响新生儿脑生长和发育，其病程中伴随的慢性亚致死性缺氧是引起极低体质量早产儿远期脑损伤和脑瘫等神经系统并发症的重要因素之一。动物研究发现慢性缺氧导致新生鼠脑皮层下和胼胝体白质损伤、进行性脑室扩大和胶质增生，突触发育前后失衡及神经递质传导障碍，从而可能显著影响感觉、运动及认知等脑功能发育。

With the advance of modem neonatal management, the increase of survival of infants born with ELBW has resulted in collateral increase in incidence of infants with serious chronic lung disease,typically bronchopulmonary dysplasia （BPD）. Long-term sensory, motor and cognitive impairments are common outcomes in survivals with moderate and severe BPD and may persist during school years and adolescence. Increasing evidence suggest that BPD exerts a significant effect on brain growth and development and may be associated with chronic sublethal hypoxia which compond the risk of extended brain injury and NS complications such as cerebral palsy. Animal studies have demonstrated progressive gliosis and cerebral ventriculomegaly, injured subcortical white matter and corpus callosum, dysynchrony synaptic development and disrupted neurotransmitssion in the hypoxia newborn brain. In this literature we built upon the review of neurogical and congnitive outcome in preterm infants with BPD and structural, functional and neuroehemical altemtions in ainimals following clinical and experimental hypoxia respoctivdy, which may underlie the primary or potential role for chronic sublethal hypoxia on premature brain development.