Analgesic effects of spinal cord peptide factors produced during the establishment and development of generators of pathologically enhanced excitation in the rat spinal cord

In rats with a pain syndrome caused by the production of a generator of pathologically enhanced excitation, substances of peptide nature with analgesic properties were found to be produced in the nociceptive system of the spinal cord. Spinal cord extracts derived from rats with such syndromes (pain syndrome of spinal origin or adjuvant arthritis) exerted analgesic effects when injected intraventricularly into recipient rats with a pain syndrome of spinal origin. The highest analgesic activity was displayed by extracts obtained from the region where the generator of pathologically enhanced excitation had been set up. The analgesic activity of the extracts was directly related to the severity and duration of the pain syndrome in the donor rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N^no 10, pp. 374–377, October, 1994