Role of the nucleus raphe obscurus in the inhibition of rostral ventrolateral medullary neurones induced by stimulation in the ventrolateral periaqueductal grey matter of the rabbit.
Experiments have been carried out to investigate the pathways which mediate the inhibitory influence of the ventrolateral periaqueductal grey matter (vlatPAG) on neurones in the rostral ventrolateral medulla (RVLM). In anaesthetized rabbits, 20-ms trains of electrical stimulation in the vlatPAG inhibited ongoing activity of neurones in the RVLM to < 30% of the control level. The inhibition was blocked after microinjections of 500-1000 nl local anaesthetic (4% lignocaine, n = 9) or 0.2 M glycine (n = 4) into nucleus raphe obscurus (NRO). We suggest that the inhibitory influence of the vlatPAG on neurones in the RVLM is mediated by a relay in NRO.
Zhang
Y M
YM
Department of Physiology, Shanghai Medical University, China.
Li
P
P
Lovick
T A
TA
D000818:Animals; D004558:Electric Stimulation; D004566:Electrodes; D005998:Glycine / Q000008:administration & dosage / Q000494:pharmacology; D008012:Lidocaine / Q000494:pharmacology; D008526:Medulla Oblongata / Q000033:anatomy & histology / Q000166:cytology / Q000502:physiology*; D008845:Microinjections; D009434:Neural Pathways / Q000187:drug effects / Q000502:physiology; D010487:Periaqueductal Gray / Q000033:anatomy & histology / Q000502:physiology*; D011817:Rabbits; D011903:Raphe Nuclei / Q000502:physiology*
D008012:Lidocaine; D005998:Glycine