Pyramidal tract effects on interneurons in the cat lumbar dorsal horn.

Publisher Website
Google Scholar
Abstract
The pyramidal tract (PT) of "guillotined" and decerebrate cats was stimulated at medullary levels and the effects on the spontaneous and peripherally evoked activity of lumbar dorsal horn cells investigated. These interneurons were grouped into layers on the basis of their anatomical location and their extracellularly recorded responses to natural stimulation. Layer 4 cells were found in Rexed''s lamina 4 and responded to cutaneous stimulation over small receptive fields; PT stimulation inhibited over 2/3 of the layer 4 cells. Layer 5 cells were located in lamina 5 and responded to skin stimulation over large fields; PT volleys inhibited 1/3, excited 1/3 and produced mixed excitation and inhibition in 1/5 of the layer 5 cells. Layer 6 cells, in lamina 6, often responded to joint movement as well as cutaneous stimulation over wide ipsilateral fields; PT stimulation excited about 2/3 of these cells. PT stimulation also evoked dorsal root potentials, whose negative phase correlated with inhibition of evoked responses in many later 4 and 5 cells.

This publication has 3 references indexed in Scilit: