[The effect of stimulation of the central gray substance on the neuronal activity of the trigeminal nerve nucleus].

Stimulation of different central gray matter areas (CGM) has been estimated comparatively for its study on the neuronal activity of the trigeminal nucleus during nociceptive stimulation prior to and after the section of the medial brain stem structures between the CGM caudal part and the dorsal raphe nucleus. The possible role of the opiate and nonopiate systems in the mechanism of inhibition of the nociceptive afferentation has been also considered. Experimental data show that in the regulation of the nociceptive afferentation the CGM is a functionally nonuniform structure: in addition to the pain-suppressing system, there is also the pain-relieving system there: inhibitory influence of different CGM areas is accomplished by both the opiate and nonopiate system; the opiate inhibition is mediated by activation of neurons of the raphe nucleus, while the nonopiate one by recruitment of the lateral pathways or activation of the rostral structures of the brain.