[Neurophysiological analysis of analgesic effect of phentanyl and moradol].

The central mechanisms of analgesic action of phentanyl and moradol are compared using analysis of changes in the early and late components of somatosensory evoked potentials (SSEP) of the brain in normal volunteers in response to pain stimulation. Phentanyl and moradol differently affect the changes in the early components of SSEP: phentanyl reduces their amplitude, whereas moradol increases it. Both drugs similarly influenced changes in the late components of SSEP. Specific effects of the drugs on the sensory and psychoemotional components of pain perception by man are discussed.