11. The effects of peripheral nerve conditioning stimuli on responses of lumbar spinal cord neurons to noxious thermal stimulation of the skin in the cat

• Published in: Philosophical transactions of the Royal Society of London. Series B, Biological sciences Biological sciences, 1985-02, Vol.308 (1136), p.417-417
• Main Author: Morris, R.
• Format: Article
• Language: English
• ISSN: 0080-4622; 2054-0280
• DOI: 10.1098/rstb.1985.0051

Consideration of the stimulus intensities and evoked sensations produced by pain relieving transcutaneous nerve stimulation (TENS) and acupuncture suggests that a wide range of primary afferents may be involved. High frequency (over 50 Hz), low intensity TENS probably only activates large mechanoreceptive primary afferents innervating skin, whereas low frequency, higher intensity TENS (Eriksson et al. 1979) and acupuncture will also activate other types of primary afferent from skin and deeper tissues. Studies in spinal cats have shown that conditioning stimuli applied to muscle nerve at intensities that would evoke group III (Sjölund et al. 1979) and C fibre (Chung et al. 1983) afferents, will inhibit reflex responses to cutaneous nerve stimulation at intensities which would evoke C fibre activity. These preliminary experiments have been carried out to examine the effects of various intensities and frequencies of peripheral nerve, particularly muscle nerve, stimulation, on responses of lumbar spinal cord neurons to noxious thermal stimulation of the skin.