Tashiro Akimasa, Bereiter David A
Department of Physiology, National Defense Medical College.
Department of Diagnostic and Biological Sciences, University of Minnesota School of Dentistry.
J Oral Sci. 2020 Mar 28;62(2):150-155. doi: 10.2334/josnusd.19-0405. Epub 2020 Mar 4.
The signs and symptoms of persistent temporomandibular joint (TMJ)/muscle disorder (TMJD) pain suggest the existence of a central neural dysfunction or a problem of pain amplification. The etiology of chronic TMJD is not known; however, female sex hormones have been identified as significant risk factors. Converging lines of evidence indicate that the junctional region between the trigeminal subnucleus caudalis (Vc) and the upper cervical spinal cord, termed the Vc/C1-2 region, is the primary site for the synaptic integration of sensory input from TMJ nociceptors. In this paper, the mechanisms behind the estrogen effects on the processing of nociceptive inputs by neurons in the Vc/C1-2 region reported by human and animal studies are reviewed. The Vc/C1-2 region has direct connections to endogenous pain and autonomic control pathways, which are modified by estrogen status and are suggested to be critical for somatomotor and autonomic reflex responses of TMJ-related sensory signals.
持续性颞下颌关节（TMJ）/肌肉紊乱（TMJD）疼痛的体征和症状表明存在中枢神经功能障碍或疼痛放大问题。慢性TMJD的病因尚不清楚；然而，女性性激素已被确定为重要的风险因素。越来越多的证据表明，三叉神经尾侧亚核（Vc）与颈上脊髓之间的交界区域，即Vc/C1-2区域，是TMJ伤害感受器感觉输入突触整合的主要部位。本文综述了人和动物研究报道的雌激素对Vc/C1-2区域神经元伤害性输入处理影响的机制。Vc/C1-2区域与内源性疼痛和自主控制通路有直接联系，这些通路会因雌激素状态而改变，并被认为对TMJ相关感觉信号的躯体运动和自主反射反应至关重要。
