Abstract：
Dynorphin is an endogenous opiate localized in many brain regions and spinal cord, but the activity of dynorphin neurons during sleep is unknown. Dynorphin is an inhibitory neuropeptide that is coreleased with orexin, an excitatory neuropeptide. We used microendoscopy to test the hypothesis that, like orexin, the dynorphin neurons are wake-active. Dynorphin-cre mice (n = 3) were administered rAAV8-Ef1a-Con/Foff 2.0-GCaMP6M into the zona incerta-perifornical area, implanted with a GRIN lens (gradient reflective index), and electrodes to the skull that recorded sleep. One month later, a miniscope imaged calcium fluorescence in dynorphin neurons during multiple bouts of wake, non-rapid-eye movement (NREM), and rapid-eye movement (REM) sleep. Unbiased data analysis identified changes in calcium fluorescence in 64 dynorphin neurons. Most of the dynorphin neurons (72%) had the highest fluorescence during bouts of active and quiet waking compared to NREM or REM sleep; a subset (20%) were REM-max. Our results are consistent with the emerging evidence that the activity of orexin neurons can be classified as wake-max or REM-max. Since the two neuropeptides are coexpressed and coreleased, we suggest that dynorphin-cre-driven calcium sensors could increase understanding of the role of this endogenous opiate in pain and sleep.
摘要：
强啡肽是一种内源性阿片类药物，位于许多脑区和脊髓，但是睡眠期间强啡肽神经元的活动是未知的。强啡肽是一种与食欲素共同释放的抑制性神经肽，一种兴奋性神经肽。我们使用显微内窥镜来检验假设，像食欲素,强啡肽神经元是唤醒活跃的。将强啡肽-cre小鼠（n=3）施用rAAV8-Ef1a-Con/Foff2.0-GCaMP6M到孔周区域，植入GRIN透镜（梯度反射指数），头骨和电极记录睡眠。一个月后,在多次苏醒期间，微镜在强啡肽神经元中成像钙荧光，NREM,REM睡眠无偏数据分析确定了64个强啡肽神经元中钙荧光的变化。与NREM或REM睡眠相比，大多数强啡肽神经元（72％）在活跃和安静的觉醒中具有最高的荧光；一个子集（20％）是REM-max。我们的结果与新出现的证据一致，即食欲素神经元的活性可以归类为wake-max或REM-max。由于两种神经肽共表达和共释放，我们建议强啡肽-cre驱动的钙传感器可以增加对这种内源性阿片类药物在疼痛和睡眠中的作用的理解.
