Effect of nucleus raphe magnus stimulation on recurrent inhibition of the monosynaptic reflex in the cat.
Experiments were performed on 8 cats anesthetized with urethan-chloralose. The effects of nucleus raphe magnus (NRM) conditioning stimulation on recurrent inhibition of posterior biceps semitendinosus nerve (PBSt) monosynaptic reflex elicited by electric stimulation of a part of L7 ventral root were investigated in the cat. It was found that (1) the PBSt monosynaptic reflex was facilitated by NRM conditioning stimulation at 30, 50 and 80 ms conditioning-test stimulus intervals, but that (2) the inhibited monosynaptic reflex by recurrent inhibition was further inhibited by NRM conditioning stimulation at the same conditioning-test stimulus intervals, and that (3) the activity of Renshaw cells as recorded by glass microelectrode was enhanced by NRM conditioning stimulation. These facts indicated that recurrent inhibition pathways are enhanced by NRM conditioning stimulation.
Wada
N
N
Department of Physiology, School of Medicine, Chiba University, Japan.
Yawashima
Y
Y
Nakajima
Y
Y
D000818:Animals; D002415:Cats; D004558:Electric Stimulation; D005260:Female; D008297:Male; D009433:Neural Inhibition; D011903:Raphe Nuclei / Q000502:physiology*; D012023:Reflex, Monosynaptic / Q000502:physiology*