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Updated: Mar 21, 2026

Parallel Measurement of Circadian Clock Gene Expression and Hormone Secretion in Human Primary Cell Cultures
Published on: November 11, 2016
Hypothalamic clock governs circadian pain
Hong-Rui Wei1,2, Qianqian Lou1, Le-Xian Li1
1Department of Anesthesiology, The First Affiliated Hospital of USTC, Center for Advanced Interdisciplinary Science and Biomedicine of IHM, Hefei National Laboratory for Physical Sciences at the Microscale, Division of Life Sciences and Medicine, University of Science and Technology of China, Hefei, PR China.
Abstract:
Chronic pain exhibits circadian rhythms in humans, but the mechanisms underlying such rhythmicity remain unclear. Here, we found daily oscillations in the nociceptive thresholds in a mouse model of neuropathic pain, driven by a rhythmic circuit from the master clock in the hypothalamus to the descending analgesia system. In the daytime (resting phase), higher vasoactive intestinal peptide (VIP) neuronal activity in suprachiasmatic nucleus (SCNVIP) activates a signaling pathway involving the paraventricular nucleus (PVN) and the ventrolateral periaqueductal gray (vlPAG), ultimately increasing nociceptive sensitivity. At night (active phase), reduced SCNVIP neuronal activity decreases pain sensitivity through this polysynaptic circuit. This study identified a circuit for regulating pain rhythmicity that might be targeted to improve chronic pain management.
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