Department of Obstetrics and Gynaecology, The Canadian Institutes of Health Research Group in Fetal and Neonatal Health and Development, Children's Health Research Institute, The University of Western Ontario, London, Ontario, Canada.
Brain Res. 2011 Jul 21;1402:38-45. doi: 10.1016/j.brainres.2011.05.043. Epub 2011 May 25.
We have studied the maturation of electrocortical (ECoG) activity in fetal sheep and the impact of chronic hypoxemia using a growth restriction model with placental embolizations. Twenty chronically catheterized fetal sheep (control, n=9; hypoxemic, n=11) were monitored at 116-119, 121-126 and 128-134 days gestational age (term=145 days), with ECoG activity scored using automated analysis of amplitude and frequency components to distinguish low-voltage/high frequency (LV/HF) and high-voltage/low frequency (HV/LF) state epochs, along with indeterminate voltage/frequency (IV/F) and transition period activities. We have shown that multiple aspects of ECoG state activity in the ovine fetus undergo maturational change as electrophysiologic measures of brain development. With chronic fetal hypoxemia, some maturational changes continue to occur, i.e. ECoG activity amplitude and 95% SEF, indicating the resiliency of these parameters to adverse conditioning. However, some maturational changes were altered, i.e. LV/HF and HV/LF incidence and duration, and likely regulated and adaptive with a decrease in the brain's nonessential energy needs, while some were altered, i.e. IV/F incidence and duration, and state transition times, and likely indicating a degree of aberrant development in associated control circuitries. This may then have consequences for disturbed sleep-wake patterns during later life and for adverse neurologic sequelae known to be increased in humans born with growth restriction.
我们研究了用电极脑电图（ECoG）活性在胎儿羊成熟和慢性低氧血症的影响使用胎盘栓塞生长受限模型。二十只慢性导管胎儿羊（对照组，n=9；低氧组，n=11）在 116-119、121-126 和 128-134 天妊娠期（足月=145 天）进行监测，使用振幅和频率成分的自动分析来对 ECoG 活动进行评分，以区分低电压/高频率（LV/HF）和高电压/低频率（HV/LF）状态期，以及不定电压/频率（IV/F）和过渡时期活动。我们表明，羊胎儿 ECoG 状态活动的多个方面作为脑发育的电生理测量经历成熟变化。在慢性胎儿低氧血症中，一些成熟变化继续发生，即 ECoG 活动幅度和 95%SEF，表明这些参数对不利条件的弹性。然而，一些成熟变化发生改变，即 LV/HF 和 HV/LF 的发生率和持续时间，可能与大脑非必需能量需求的减少有关，而一些成熟变化发生改变，即 IV/F 的发生率和持续时间以及状态转换时间，可能表明相关控制回路存在一定程度的异常发育。这可能会对以后生活中的睡眠-觉醒模式产生干扰，并对已知在生长受限的人类中增加的不良神经后果产生影响。
