title: Suppression of the nociceptive jaw-opening reflex by stimulation of the red nucleus.
abstract: We studied the effect of stimulation of the red nucleus (RN) on the jaw-opening reflex (JOR) in anesthetized rats. The JOR was evoked by electrical stimulation of the tooth pulp of a lower incisor, and was recorded as the electromyographic responses of the anterior belly of the digastric muscle, bilaterally. Conditioning electrical stimulation of the RN was found to suppress the JOR bilaterally. Microinjection of monosodium glutamate into the RN also suppressed the JOR bilaterally. The suppressive effect of the magnocellular part of the RN was significantly larger than that of the parvicellular part of the RN. These results imply that the RN is involved in control of the JOR evoked by noxious stimulus.
authors.affiliation: Department of Orthodontics, The Nippon Dental University, School of Life Dentistry at Niigata, 1-8 Hamaura-cho, Chuou-ku, Niigata 951-8580, Japan.
authors.forename: Eriko
authors.initials: E
authors.lastname: Yajima
authors.forename: Yoshihide
authors.initials: Y
authors.lastname: Satoh
authors.forename: Ken'Ichi
authors.initials: K
authors.lastname: Ishizuka
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Iwasaki
authors.forename: Kazuto
authors.initials: K
authors.lastname: Terada
mesh_terms: D000818:Animals; D003782:Dental Pulp / Q000294:innervation; D004558:Electric Stimulation; D007568:Jaw / Q000502:physiology*; D008297:Male; D059225:Nociception / Q000502:physiology*; D010146:Pain / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012012:Red Nucleus / Q000502:physiology*; D012018:Reflex / Q000502:physiology*