Gentle M J
Roslin Institute of Edinburgh, Midlothian, Scotland, UK.
Pain. 1997 Apr;70(2-3):245-51. doi: 10.1016/s0304-3959(97)03324-6.
The physiological properties of joint capsule mechanoreceptors in the ankle joint of the chicken were studied in the 3-h period immediately after intra-articular injection of microcrystal sodium urate. The electrical activity was recorded from single C- and A-delta sensory fibres dissected from the parafibular nerve. C-fibres showed high levels of spontaneous activity and receptive fields that varied from single spots 1 mm in diameter up to 4 x 4 mm. Thresholds to mechanical stimulation ranged from 0.1 to 8 g and 80% of the units responded to movement of the joint. A-delta fibres showed little spontaneous activity and receptive fields that varied from 1 mm to 9 x 1 mm. Thresholds to mechanical stimulation ranged from 0.1 to 16 g and 17% responded to joint movement. A comparison of the physiological properties of the C- and A-delta fibres in sodium urate arthritis with similar fibres in normal and monoarthritic animals indicated an increased sensitivity in the C-fibres but not in the A-delta fibres. Sensitisation was observed in the significantly increased receptive field size, decreased response thresholds, increased response to joint movement and the high level of spontaneous activity. These changes in the sensitivity of the joint capsule C-fibre receptors provides peripheral neural evidence for the pain experienced in acute gouty arthritis.
在关节腔内注射微晶尿酸钠后的3小时内，对鸡踝关节关节囊机械感受器的生理特性进行了研究。从腓骨旁神经分离出的单根C纤维和A-δ感觉纤维记录电活动。C纤维表现出高水平的自发活动，其感受野直径从1毫米的单个点到4×4毫米不等。对机械刺激的阈值范围为0.1至8克，80%的单位对关节运动有反应。A-δ纤维表现出很少的自发活动，其感受野从1毫米到9×1毫米不等。对机械刺激的阈值范围为0.1至16克，17%对关节运动有反应。将尿酸钠性关节炎中C纤维和A-δ纤维的生理特性与正常和单关节炎动物中的类似纤维进行比较，结果表明C纤维的敏感性增加，而A-δ纤维没有。在感受野大小显著增加、反应阈值降低、对关节运动的反应增加以及自发活动水平高等方面观察到了敏化现象。关节囊C纤维感受器敏感性的这些变化为急性痛风性关节炎中所经历的疼痛提供了外周神经证据。
