Pain and vascular reflexes in man elicited by prolonged noxious mechano-stimulation

摘要: Abstract Interdigital webs of the hands human volunteers were pinched for periods 2 min duration to induce tonic pain perceptions. During stimulation, subjects gave estimates their level at 10-sec intervals on a visual analogue scale, and stimulus induced changes skin blood flow in stimulated hand was assessed by photo-plethysmography. Sustained pinching reflex vasoconstriction with rather slow adaptation rate no signs habituation between trials. Step increases force course reflected decrease plethysmogram amplitude as well increased ratings, although usually unaware these steps. Lowering strength opposite, albeit much smaller effects both ratings vascular reactions. It is concluded that vasomotor responses described this paper are mediated nociceptor input reflect processing mainly spinal level.