Yoshizato T, Koyanagi T, Takashima T, Satoh S, Akazawa K, Nakano H
Department of Gynecology and Obstetrics Faculty of Medicine, Kyushu University, Fukuoka, Japan.
Early Hum Dev. 1994 Feb;36(2):101-12. doi: 10.1016/0378-3782(94)90037-x.
We attempted to identify the brain segment which controls heart rate changes in human fetuses with advancing gestation. Twelve anencephalic and 165 normal fetuses (control-group fetuses) between 25-32 weeks' gestation were studied. The instantaneous fetal heart rate (FHR) data were obtained from each fetus for a continuous 90-120 min period, using an external cardiotocograph. Calculations included the 'individual probability distribution matrices' in which the FHRs at 1 beat/min intervals between 110 and 180 beats/min, the beat-to-beat differences (DFHRs) between +/- 5 beats/min and the probability values were arranged in rows, columns and the corresponding elements, respectively. Using 2-gestational-week intervals probability distribution matrices (age-group probability distribution matrices) obtained from 335 normal fetuses in our previous study as a reference, the difference between a given 'individual probability distribution matrix' and the corresponding age-group probability distribution matrix' was quantified as the 'difference rate' according to the formula in the text. From 25-26 to 27-28 weeks' gestation, the 'difference rates' in four anencephalic fetuses, with only the spinal cord preserved, were significantly higher in value than those of control-group fetuses, whereas the rates in four fetuses with both the spinal cord and medulla oblongata preserved, indicated no significant differences. From 29-30 to 31-32 weeks' gestation, the rates of the four fetuses with the spinal cord and medulla oblongata preserved, showed significant differences from the control-group fetuses. These findings suggest that there is a critical period between 27-28 and 29-30 weeks' gestation with regard to the developing brain function pertaining to FHR changes. In the early stage, the medulla oblongata plays a role in FHR changes, whereas, in the latter stage, the brain cephalad to the medulla also appears to take on the role of FHR regulator.
我们试图确定随着孕周增加，控制人类胎儿心率变化的脑区。研究了12例无脑儿胎儿和165例孕25 - 32周的正常胎儿（对照组胎儿）。使用外部胎心监护仪，对每个胎儿连续90 - 120分钟获取瞬时胎儿心率（FHR）数据。计算包括“个体概率分布矩阵”，其中110至180次/分钟之间以1次/分钟间隔的FHR、±5次/分钟之间的逐搏差异（DFHRs）以及概率值分别排列在行、列和相应元素中。以前一项研究中从335例正常胎儿获得的以2周孕期间隔的概率分布矩阵（年龄组概率分布矩阵）作为参考，根据文中公式将给定的“个体概率分布矩阵”与相应的年龄组概率分布矩阵之间的差异量化为“差异率”。在孕25 - 26周到27 - 28周期间，4例仅保留脊髓的无脑儿胎儿的“差异率”值显著高于对照组胎儿，而4例同时保留脊髓和延髓的胎儿的“差异率”无显著差异。在孕29 - 30周到31 - 32周期间，4例保留脊髓和延髓的胎儿的“差异率”与对照组胎儿有显著差异。这些发现表明，在孕27 - 28周和29 - 30周之间存在一个与FHR变化相关的脑功能发育的关键时期。在早期，延髓在FHR变化中起作用，而在后期，延髓以上的脑区似乎也承担了FHR调节者的角色。
