Li Chun-Yuan, Morrow Thomas J, Casey Kenneth L
Departments of Physiology, University of Michigan, and Neurology Research Laboratories (Neurophysiology), Veterans Administration Medical Center, Ann Arbor, MI 48105 U.S.A. Neurology, University of Michigan, and Neurology Research Laboratories (Neurophysiology), Veterans Administration Medical Center, Ann Arbor, MI 48105 U.S.A.
Pain. 1985 Jan;21(1):17-24. doi: 10.1016/0304-3959(85)90072-7.
Previous experiments have shown that cats respond to noxious thermal pulse stimulation of the upper hind limb at an average latency of 2.3 sec. To determine if C fiber afferents could mediate this response, we recorded the response latency and threshold of single fibers of cat femoral cutaneous nerve to the same stimuli used in the behavioral experiments. Of 28 C fibers tested, 10 (36%) responded to heating; 4 (17%) of 24 fibers with conduction velocities of 2.5-30 m/sec responded to heat. All fibers but one discharged within 1.0 sec of thermal pulse onset (median: 800 msec) at an average and median threshold of 46 degrees C. Thermal nociceptors with C fiber afferents could mediate the initiation of behavioral nocifensive responses to heat in the cat.
先前的实验表明,猫对后肢上部的有害热脉冲刺激的平均反应潜伏期为2.3秒。为了确定C类纤维传入神经是否能介导这种反应,我们记录了猫股皮神经单纤维对行为实验中使用的相同刺激的反应潜伏期和阈值。在测试的28根C类纤维中,10根(36%)对加热有反应;在传导速度为2.5 - 30米/秒的24根纤维中,4根(17%)对热有反应。除一根纤维外,所有纤维在热脉冲开始后1.0秒内(中位数:800毫秒)放电,平均阈值和中位数阈值为46摄氏度。具有C类纤维传入神经的热伤害感受器可能介导猫对热的行为伤害性防御反应的启动。