中国神经再生研究(英文版) ›› 2023, Vol. 18 ›› Issue (11): 2466-2473.doi: 10.4103/1673-5374.371382

• 原著:神经损伤修复保护与再生 • 上一篇    下一篇

单侧脊神经结扎非人灵长类动物疼痛相关脑区激活的潜在性别差异

  

  • 出版日期:2023-11-15 发布日期:2023-05-04

Potential sex differences in activation of pain-related brain regions in nonhuman primates with a unilateral spinal nerve ligation

Kanae Murata1, Kenya Nozawa1, Mayumi Matsushita1, Aozora Yamashita1, Rintaro Fujii1, Yuji Awaga1, Aldric Hama1, *, #br# Takahiro Natsume1, Go Yoshida2, Yukihiro Matsuyama2, Hiroyuki Takamatsu1#br#   

  1. 1Hamamatsu Pharma Research, Inc., Hamamatsu, Shizuoka, Japan; 2Department of Orthopedic Surgery, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, Japan
  • Online:2023-11-15 Published:2023-05-04
  • Contact: Aldric Hama, PhD, aldric-hama@hpharma.jp.

摘要:

当前,临床中缺少强力的慢性疼痛镇痛剂的部分原因是缺乏反映临床疼痛状态的动物模型。实验用功能磁共振成像观察了雄性和雌性食蟹猴单侧L7脊神经结扎后,刺激诱发的大脑激活以及临床镇痛药普瑞巴林、度洛西汀和吗啡对食蟹猴大脑激活的影响。用改良的直腿抬高试验评估清醒食蟹猴的疼痛严重程度,并诱发麻醉动物的区域脑激活和观察临床镇痛剂对清醒疼痛行为和区域大脑激活的潜在影响。在脊神经结扎之后,雄性和雌性食蟹猴都表现出同侧直腿抬高阈值的明显下降,这表明存在着神经根性疼痛。吗啡干预增加了雄性和雌性食蟹猴的直腿抬高阈值,而度洛西汀和普瑞巴林却没有。在雄性食蟹猴中,患侧直腿抬高激活了对侧岛叶和体感皮质以及丘脑。在雌性食蟹猴中,同侧直腿抬高激活了扣带回皮质和对侧岛叶和体感皮质。对侧直腿抬高未引起大脑激活。吗啡减少了雄性和雌性食蟹猴的所有脑区的激活程度。在雄性食蟹猴中,普瑞巴林和度洛西汀均未降低大脑激活程度。然而,在雌性食蟹猴中,普瑞巴林和度洛西汀则降低了扣带回皮质的激活程度。结果表明,周围神经损伤后,脑区的激活程度存在性别差异。大脑激活的性别差异性可能对临床慢性疼痛感知和对镇痛剂反应产生不同的影响。未来的神经性疼痛管理方法需要考虑疼痛机制和治疗效果的潜在性别差异。

https://orcid.org/0000-0001-7372-979X (Aldric Hama)

Abstract: The lack of truly robust analgesics for chronic pain is owed, in part, to the lack of an animal model that reflects the clinical pain state and of a mechanism-based, objective neurological indicator of pain. The present study examined stimulus-evoked brain activation with functional magnetic resonance imaging in male and female cynomolgus macaques following unilateral L7 spinal nerve ligation and the effects of clinical analgesics pregabalin, duloxetine, and morphine on brain activation in these macaques. A modified straight leg raise test was used to assess pain severity in awake animals and to evoke regional brain activation in anesthetized animals. The potential effects of clinical analgesics on both awake pain behavior and regional brain activation were examined. Following spinal nerve ligation, both male and female macaques showed significantly decreased ipsilateral straight leg raise thresholds, suggesting the presence of radicular-like pain. Morphine treatment increased straight leg raise thresholds in both males and females whereas duloxetine and pregabalin did not. In male macaques, the ipsilateral straight leg raise activated contralateral insular and somatosensory cortex (Ins/SII), and thalamus. In female macaques, the ipsilateral leg raise activated cingulate cortex and contralateral insular and somatosensory cortex. Straight leg raises of the contralateral, unligated leg did not evoke brain activation. Morphine reduced activation in all brain regions in both male and female macaques. In males, neither pregabalin nor duloxetine decreased brain activation compared with vehicle treatment. In females, however, pregabalin and duloxetine decreased the activation of cingulate cortex compared with vehicle treatment. The current findings suggest a differential activation of brain areas depending on sex following a peripheral nerve injury. Differential brain activation observed in this study could underlie qualitative sexual dimorphism in clinical chronic pain perception and responses to analgesics. Future pain management approaches for neuropathic pain will need to consider potential sex differences in pain mechanism and treatment efficacy.

Key words: biomarkers, functional magnetic resonance imaging, lumbar radicular pain, Macaca fascicularis, neuroimaging, neuropathic pain, sciatica, straight leg raise