Bocking A D, Harding R, Wickham P J
J Dev Physiol. 1985 Feb;7(1):47-54.
Accelerations in fetal heart rate have been shown to be closely related to fetal body movements and are indicative of well-being in the human fetus. We have examined the association of accelerations and decelerations in heart rate with skeletal muscle activity in 8 fetal sheep between 125 and 145 days' gestation. Accelerations/decelerations were defined as transient increases/decreases in fetal heart rate of greater than or equal to 10 beats/min. lasting for 5 s or longer. For accelerations (n = 1180), the mean duration was 18.8 +/- 1.5 s (SEM) and the mean amplitude was 25.3 +/- 1.2 beats/min; for decelerations (n = 237), the mean duration was 17.4 +/- 1.6 s and the mean amplitude was 18.7 +/- 1.0 beats/min. Electromyograms were recorded from the nuchal muscles and antagonistic muscle groups of the fetal forelimb and hindlimb. Electromyogram activity occurred during 88.4 +/- 2.8% of accelerations and 60.6 +/- 7.7% of decelerations. There was a 36.6% reduction in the number of accelerations following fetal paralysis with gallamine, but no change in their amplitude or duration. It is concluded that accelerations in heart rate are highly associated with skeletal muscle activity in fetal sheep. The majority of these occur as a result of central neuronal output rather than as a consequence of fetal movement.
胎儿心率加速已被证明与胎儿身体活动密切相关，是人类胎儿健康的指标。我们研究了125至145天妊娠期的8只胎羊心率加速和减速与骨骼肌活动的关联。加速/减速定义为胎儿心率瞬时增加/减少大于或等于10次/分钟，持续5秒或更长时间。对于加速（n = 1180），平均持续时间为18.8 +/- 1.5秒（标准误），平均幅度为25.3 +/- 1.2次/分钟；对于减速（n = 237），平均持续时间为17.4 +/- 1.6秒，平均幅度为18.7 +/- 1.0次/分钟。从胎儿颈部肌肉以及前肢和后肢的拮抗肌群记录肌电图。肌电图活动出现在88.4 +/- 2.8%的加速期间和60.6 +/- 7.7%的减速期间。用加拉明使胎儿麻痹后，加速次数减少了36.6%，但其幅度或持续时间没有变化。结论是，胎羊心率加速与骨骼肌活动高度相关。其中大多数是中枢神经元输出的结果，而非胎儿运动的结果。
