Cote A, Haddad G G
Department of Pediatrics (Respiratory Medicine Service), Montreal Children's Hospital, Qc, Canada.
Pediatr Res. 1990 Sep;28(3):218-22. doi: 10.1203/00006450-199009000-00012.
The regional distribution of blood flow to the brain and to other major organs was studied during wakefulness and sleep in growing piglets. A young group was studied at 6.8 +/- 1.3 d of age and an older group at 33.5 +/- 5.5 d. Two d before the experiments, we instrumented the animals for measurement of blood flow by the microsphere technique. We determined sleep state using EEG and behavioral criteria. Although we did not find significant differences in blood gas tensions and cardiac output with changes in behavioral states, we did note a number of important changes in brain and muscle blood flow with sleep. 1) Although total brain blood flow changed little between wakefulness and sleep at both ages, regional differences existed. Indeed, at both ages, during rapid eye movement sleep (active sleep), blood flow to the thalamus-hypothalamus and brainstem was significantly higher than during wakefulness (p less than 0.025); in older piglets, blood flow to these two regions was significantly lower in quiet sleep than in wakefulness (p less than 0.05). 2) Blood flow to most skeletal muscle groups, and particularly to the diaphragm, was lower during sleep than during wakefulness. 3) Age did not have a significant effect on the regional distribution of blood flow during sleep. We conclude that behavioral states influence the regional distribution of blood flow in early life, but not in an age-dependent fashion. We speculate that, because no difference was observed in other hemodynamic variables, the regional changes in organ blood flow with sleep most probably reflect the differences in local metabolic needs.
在生长中的仔猪清醒和睡眠期间，研究了其脑部及其他主要器官的血流区域分布情况。研究了一个幼龄组（6.8±1.3日龄）和一个老龄组（33.5±5.5日龄）。在实验前2天，我们通过微球技术对动物进行仪器安装以测量血流。我们使用脑电图和行为标准来确定睡眠状态。虽然我们没有发现血气张力和心输出量随行为状态的变化有显著差异，但我们确实注意到睡眠时脑和肌肉血流有一些重要变化。1）虽然两个年龄段在清醒和睡眠期间全脑血流变化不大，但存在区域差异。实际上，在两个年龄段，快速眼动睡眠（主动睡眠）期间丘脑 - 下丘脑和脑干的血流显著高于清醒时（p<0.025）；在老龄仔猪中，安静睡眠时这两个区域的血流显著低于清醒时（p<0.05）。2）大多数骨骼肌群，尤其是膈肌的血流在睡眠时低于清醒时。3）年龄对睡眠期间血流的区域分布没有显著影响。我们得出结论，行为状态影响生命早期血流的区域分布，但并非以年龄依赖的方式。我们推测，由于在其他血流动力学变量中未观察到差异，睡眠时器官血流的区域变化很可能反映了局部代谢需求的差异。
