Lesions rostral and caudal to the trigeminal motor nucleus and their effects on the jaw-opening reflex of the cat.
Brain stem lesions placed immediately rostral to the trigeminal motor nucleus of the cat abolish the visible jaw-opening reflex produced by electrical stimulation of the periodontal ligaments. These lesions also greatly diminish the amplitude of the electromyographic response recorded from the anterior belly of the digastric muscle. This attenuation could not be modified by injections of systemic strychnine (a glycine antagonist). Lesions placed immediately caudal to the trigeminal motor nucleus also abolished the visible reflex and greatly reduced the amplitude of the digastric response, but in this case, the attenuated response was slightly augmented by strychnine. These data suggest that glycinergic inhibitory neurons form part of the rostral pathway that regulate jaw-opening motor neurons.
Bailey
J M
JM
Department of Anatomy, University of Mississippi Medical Center, Jackson 39216.
Capra
N F
NF
D000818:Animals; D001933:Brain Stem / Q000503:physiopathology*; D002415:Cats; D007568:Jaw / Q000503:physiopathology*; D009434:Neural Pathways / Q000502:physiology; D012018:Reflex; D013331:Strychnine / Q000502:physiology; D014278:Trigeminal Nuclei / Q000503:physiopathology*
D013331:Strychnine