Maturation of sleep homeostasis in developing rats: a role for preoptic area neurons.
Maturation of sleep homeostasis in developing rats: a role for preoptic area neurons.
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发育中大鼠睡眠稳态的成熟：视前区神经元的作用。
DOI：
10.1152/ajpregu.00727.2010
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发表时间：
2011
期刊：
影响因子：
--
通讯作者：
Szymusiak,Ronald
中科院分区：
文献类型：
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作者：
Gvilia,Irma;Suntsova,Natalia;Angara,Bryan;McGinty,Dennis;Szymusiak,Ronald
本研究评估的假设，下丘脑睡眠调节神经元回路的发育变化有助于在大鼠出生后第四周的睡眠稳态的成熟。在一项纵向研究中，我们量化了基线期间以及出生后第21/29天（P21/29）和P22/30天（实验1）睡眠剥夺（SD）时的睡眠电图测量。在P21的24小时基线记录期间，亮相和暗相的总睡眠时间（TST）没有显着差异。在P29，TST在亮相显著高于暗相。非快速眼动（NREM）睡眠发作的平均持续时间在P29比P21显著更长，表明睡眠巩固改善。在P22和P30，大鼠在恢复睡眠（RS）期间表现出增加的NREM睡眠量和NREM脑电图δ功率与基线相比。仅在P30观察到RS期间NREM睡眠时间延长。在实验2中，我们用c-Fos和谷氨酸脱羧酶（GAD）免疫组织化学方法定量了SD和RS时P22和P30大鼠正中视前核（MnPN）和腹外侧视前区（VLPO）GABA能神经元的活性。在P22大鼠中，VLPO中Fos+GAD+神经元的数量在实验条件之间没有差异。在P30大鼠，VLPO中Fos+GAD+计数在RS期间升高。MnPN神经元活性在P22大鼠中是状态依赖性的，但Fos+GAD+细胞计数在P30大鼠中更高。这些发现支持了这一假设，即视前睡眠调节神经元的功能出现有助于发育中的大鼠大脑的睡眠稳态的成熟。
The present study evaluated the hypothesis that developmental changes in hypothalamic sleep-regulatory neuronal circuits contribute to the maturation of sleep homeostasis in rats during the fourth postnatal week. In a longitudinal study, we quantified electrographic measures of sleep during baseline and in response to sleep deprivation (SD) on postnatal days 21/29 (P21/29) and P22/30 (experiment 1). During 24-h baseline recordings on P21, total sleep time (TST) during the light and dark phases did not differ significantly. On P29, TST during the light phase was significantly higher than during the dark phase. Mean duration of non-rapid-eye-movement (NREM) sleep bouts was significantly longer on P29 vs. P21, indicating improved sleep consolidation. On both P22 and P30, rats exhibited increased NREM sleep amounts and NREM electroencephalogram delta power during recovery sleep (RS) compared with baseline. Increased NREM sleep bout length during RS was observed only on P30. Inexperiment 2, we quantified activity of GABAergic neurons in median preoptic nucleus (MnPN) and ventrolateral preoptic area (VLPO) during SD and RS in separate groups of P22 and P30 rats using c-Fos and glutamic acid decarboxylase (GAD) immunohistochemistry. In P22 rats, numbers of Fos+GAD+neurons in VLPO did not differ among experimental conditions. In P30 rats, Fos+GAD+counts in VLPO were elevated during RS. MnPN neuronal activity was state-dependent in P22 rats, but Fos+GAD+cell counts were higher in P30 rats. These findings support the hypothesis that functional emergence of preoptic sleep-regulatory neurons contributes to the maturation of sleep homeostasis in the developing rat brain.