The effects of intrathecal galanin on the activity of single wide dynamic range (WDR) spinal dorsal horn neurones were analyzed in anaesthetized adult rats. Abeta-, Adelta- and C-fibres were activated by transcutaneous electrical stimulation which also induced wind-up and post-discharge. Galanin dose-dependently (0. 15-15 nmol/50 microl) enhanced Adelta-and C-fibre evoked responses, post-discharge and wind-up. Application of (D-Thr(6), D-Trp(8, 9), 15-ol)-galanin (1-15), a putative antagonist, did not attenuate the enhanced effects evoked by galanin. (D-Thr(6), D-Trp(8, 9), 15-ol)-galanin (1-15) applied alone (0.3-30 nmol/50 microl) to a separate population of neurones inhibited Abeta responses but enhanced post-discharge and wind-up in a similar pattern to galanin. Thus, (D-Thr(6), D-Trp(8, 9), 15-ol)-galanin (1-15) behaved as an agonist in the present experiments. In conclusion, in the spinal cord of the anaesthetized rat, galanin has a purely pro-nociceptive role, since it enhanced responses evoked by high-threshold fibre stimulation, along with post-discharge and wind-up of WDR neurones.