Toossi Hanieh, Del Cid-Pellitero Esther, Jones Barbara E
Department of Neurology and Neurosurgery, Montreal Neurological Institute, McGill University , Montreal, Quebec, Canada H3A 2B4.
eNeuro. 2016 Jun 9;3(3). doi: 10.1523/ENEURO.0077-16.2016. eCollection 2016 May-Jun.
Though overlapping in distribution through the hypothalamus, orexin (Orx) and melanin-concentrating hormone (MCH) neurons play opposite roles in the regulation of sleep-wake states. Orx neurons discharge during waking, whereas MCH neurons discharge during sleep. In the present study, we examined in mice whether GABAA and GABAB receptors (Rs) are present on Orx and MCH neurons and might undergo differential changes as a function of their different activities following sleep deprivation (SD) and sleep recovery (SR). Applying quantitative stereological image analysis to dual-immunofluorescent stained sections, we determined that the proportion of Orx neurons positively immunostained for GABAARs was significantly higher following SD (∼48%) compared with sleep control (SC; ∼24%) and SR (∼27%), and that the luminance of the GABAARs was significantly greater. In contrast, the average proportion of the MCH neurons immunostained for GABAARs was insignificantly lower following SD (∼43%) compared with SC (∼54%) and SR (56%), and the luminance of the GABAARs was significantly less. Although, GABABRs were observed in all Orx and MCH neurons (100%), the luminance of these receptors was differentially altered following SD. The intensity of GABABRs in the Orx neurons was significantly greater after SD than after SC and SR, whereas that in the MCH neurons was significantly less. The present results indicate that GABA receptors undergo dynamic and differential changes in the wake-active Orx neurons and the sleep-active MCH neurons as a function of and homeostatic adjustment to their preceding activity and sleep-wake state.
尽管食欲素（Orx）和促黑素细胞激素（MCH）神经元在下丘脑的分布有重叠，但它们在睡眠-觉醒状态的调节中发挥着相反的作用。Orx神经元在清醒时放电，而MCH神经元在睡眠时放电。在本研究中，我们在小鼠中检测了GABAA和GABAB受体（Rs）是否存在于Orx和MCH神经元上，以及在睡眠剥夺（SD）和睡眠恢复（SR）后，它们是否会因其不同的活动而发生不同的变化。通过对双重免疫荧光染色切片应用定量体视学图像分析，我们确定，与睡眠对照（SC；约24%）和睡眠恢复（SR；约27%）相比，SD后对GABAARs呈阳性免疫染色的Orx神经元比例显著更高（约48%），且GABAARs的亮度显著更大。相比之下，与SC（约54%）和SR（56%）相比，SD后对GABAARs呈免疫染色的MCH神经元的平均比例略低（约43%），且GABAARs的亮度显著更低。尽管在所有Orx和MCH神经元中都观察到了GABABRs（100%），但这些受体的亮度在SD后有不同程度的改变。SD后Orx神经元中GABABRs的强度显著高于SC和SR后，而MCH神经元中的强度则显著更低。目前的结果表明，GABA受体在觉醒活跃的Orx神经元和睡眠活跃的MCH神经元中会根据其先前的活动和睡眠-觉醒状态进行动态和不同的变化以及稳态调节。
