Nucleus raphe magnus inhibition of spinal cord dorsal horn neurons
HL Fields, AI Basbaum, CH Clanton, SD Anderson - Brain research, 1977 - Elsevier
HL Fields, AI Basbaum, CH Clanton, SD Anderson
Brain research, 1977•ElsevierIn decerebrate cats, electrical stimulation of nucleus raphe magnus (NRM) of the medulla
produced marked inhibition of spinal neurons in lumbosacral dorsal horn. Only neurons with
high threshold inputs were inhibited. These cells were located in lamina I and in or near
laminae V and VI. The duration of inhibition produced was related to the stimulus train
length. An ipsilateral lesion of the dorsolateral funiculus at L1 markedly reduced the
inhibition of neurons caudal to the lesion. Although NRM stimulation was the most effective …
produced marked inhibition of spinal neurons in lumbosacral dorsal horn. Only neurons with
high threshold inputs were inhibited. These cells were located in lamina I and in or near
laminae V and VI. The duration of inhibition produced was related to the stimulus train
length. An ipsilateral lesion of the dorsolateral funiculus at L1 markedly reduced the
inhibition of neurons caudal to the lesion. Although NRM stimulation was the most effective …
Abstract
In decerebrate cats, electrical stimulation of nucleus raphe magnus (NRM) of the medulla produced marked inhibition of spinal neurons in lumbosacral dorsal horn. Only neurons with high threshold inputs were inhibited. These cells were located in lamina I and in or near laminae V and VI.
The duration of inhibition produced was related to the stimulus train length. An ipsilateral lesion of the dorsolateral funiculus at L1 markedly reduced the inhibition of neurons caudal to the lesion.
Although NRM stimulation was the most effective, inhibition from more lateral sites could be obtained at higher stimulus intensities.
NRM induced inhibition is probably mediated by a direct projection via the dorsolateral funiculus to spinal dorsal horn laminae I, II, V and VI.
The results are discussed in relation to proposed mechanisms underlying the analgesia produced by NRM stimulation.
Elsevier