Peripheral neural mechanisms of cutaneous hyperalgesia following mild injury by heat.

摘要: Pain thresholds in humans were determined for heat stimulations of the skin before and after a mild injury induced by single conditioning stimulus (CS) 50 degrees C 100 sec duration. The same stimuli delivered to receptive fields fiber A mechanoheat-sensitive nociceptors (CMH AMH nociceptors, respectively) low threshold warm cold receptors anesthetized monkey CMH recorded percutaneously from peroneal nerve awake humans. normal matched only response not nociceptors. Immediately following injury, some pain elevated, but 5 10 min CS, lowered 2 6 below (hyperalgesia nociceptor sensitization). No other type cutaneous receptor studied exhibited changes similar those observed magnitude hyperalgesia sensitization monkeys greater hairy than glabrous skin. time course development was altered ischemia or conduction block fibers. results support conclusion that activity is major peripheral determinant