Changes of the Jaw Opening Reflex Activity by Electroacupuncture Stimulation in Rat

1981 ◽  
Vol 09 (03) ◽  
pp. 236-242 ◽  
Author(s):  
Kazuo Toda
Keyword(s):  
Tooth Pulp ◽  
Spinal Trigeminal Nucleus ◽  
Trigeminal Nucleus ◽  
Direct Stimulation ◽  
Lower Lip ◽  
Jaw Opening ◽  
Jaw Opening Reflex ◽  
Sensory Pathway ◽  
Main Action ◽  
Stimulation Of

After electroacupuncture stimulation applied to bilateral Ho-Ku points in the rat forepaw, jaw opening reflex to tooth pulp stimulation was fairly suppressed, but that to gingiva, upper lip or lower lip stimulation was scarely affected. By direct stimulation of afferent sensory pathway in the spinal trigeminal nucleus, jaw opening reflex was also evoked. Suppressive effects of electroacupuncture were more markedly observed when the jaw opening reflex was evoked by stimulating the caudal part of the spinal trigeminal nucleus than when the reflex was evoked by stimulation of the rostral area of the nucleus. One of the main action sites of the electroacupuncture on the jaw opening reflex was the caudal spinal trigeminal nucleus, which is the secondary neuron level in the trigeminal noxious sensory pathway, suggesting that electroacupuncture can provoke the pain suppressive effects strongly in the lower part of the brain with the higher brain function being intact. Therefore, this observation is thought to be well coincident with clinical data that acupuncture produces analgesia without affecting patients' consciousness during surgical operations.

Excitation and inhibition of neurons in the trigeminal nucleus caudalis following periaqueductal gray stimulation

1978 ◽  
Vol 56 (1) ◽  
pp. 157-161 ◽  
Author(s):  
R. K. Andersen ◽  
J. P. Lund ◽  
E. Puil
Keyword(s):  
Periaqueductal Gray ◽  
Infraorbital Nerve ◽  
Reflex Response ◽  
Tooth Pulp ◽  
Trigeminal Nucleus ◽  
Trigeminal Nucleus Caudalis ◽  
Jaw Opening ◽  
Narcotic Analgesia ◽  
Jaw Opening Reflex ◽  
Decerebrate Cats

Electrical stimulation (3–4 shocks, 300 Hz, 30–150 μA) of the periaqueductal gray matter (CG) or dorsal raphé nucleus (DR) of decerebrate cats reduced or abolished the jaw-opening reflex response evoked by stimulation of either the tooth pulp or infraorbital nerve. In addition, CG or DR stimulation inhibited the response of 12 out of 16 trigeminal nucleus caudalis neurons to activation of their sensory afferent inputs. Ten other neurons recorded in the same sites, and often at the same time, but which did not respond to the sensory inputs utilized, were excited by identical stimuli to CG or DR. This excitatory response was blocked by intravenously administered naloxone (0.1–0.2 mg/kg). It is suggested that those neurons which are excited by CG and DR stimulation may be interneurons involved in pre- and post-synaptic inhibition of sensory transmission during stimulus-produced or narcotic analgesia.

Peripheral Afferent Nerve Impulses for Conveying Electroacupuncture Effects on the Jaw Opening Reflex Evoked by Tooth Pulp Stimulation in Rat

1981 ◽  
Vol 09 (04) ◽  
pp. 319-325 ◽  
Author(s):  
Kazuo Toda
Keyword(s):  
Radial Nerve ◽  
Threshold Value ◽  
Tooth Pulp ◽  
Albino Rats ◽  
Conditioning Stimulation ◽  
Jaw Opening ◽  
Before And After ◽  
Jaw Opening Reflex ◽  
Wistar Albino Rats ◽  
Stimulation Of

Effects of conditioning electrical stimulation of the nerves innervated around the meridian Ho-Ku point on the tooth-pulp evoked jaw opening reflex were investigated in Wistar albino rats. Changes of the threshold of the reflex were monitored before and after the conditioning stimulation. The increased changes of the threshold value gradually appeared and even after the cessation of the conditioning stimulation, its effect remained for several minutes. Of the three nerves in the brachial plexus (radial, median and ulnar), radial nerve was the most effective. The ipsilateral nerve stimulation was more effective on the threshold elevation of the reflex that the contralateral one. When the two nerves were stimulated simultaneously, the increase of the threshold value was sometimes observed as compared to the case of stimulating each nerve separately. However, in cases of the combination stimulation including radial nerve, the summation among the different impulses produced by the conditioning stimulation was scarely observed: therefore, the effect was not reinforced.

Reflex Responses in Human Jaw, Lip, and Tongue Muscles Elicited by Mechanical Stimulation

1987 ◽  
Vol 30 (1) ◽  
pp. 70-79 ◽  
Author(s):  
Christine M. Weber ◽  
Anne Smith
Keyword(s):  
Mechanical Stimuli ◽  
Observable Effect ◽  
Direct Stimulation ◽  
Muscle Spindle Afferents ◽  
Lower Lip ◽  
Reflex Responses ◽  
Reflex Pathways ◽  
Tongue Muscles ◽  
Jaw Muscle ◽  
Stimulation Of

Reflex responses in human jaw, lip, and tongue muscles were elicited with brief, innocuous mechanical stimuli. Stimuli were applied to the masseter (and overlying tissue), the lower lip vermilion, and the tongue dorsum. Reflex responses occurred in masseter, orbicularis oris inferior, and genioglossus muscles upon direct stimulation of the sites associated with each of these muscles. In contrast, reflex responses to stimulation of "distant" sites occurred almost exclusively in masseter; that is, stimulation of the lip and tongue produced responses in masseter, but, stimulation of jaw muscle spindle afferents and overlying cutaneous receptors had no observable effect on activity in genioglossus or orbicularis oris inferior muscles. It could be hypothesized that the motoneuron pools controlling jaw muscles are more sensitive to synaptic inputs generated by reflex pathways originating in other structures. The sensitivity of the masseter muscle to inputs from the lip and tongue may serve to link these structures functionally.

Sign in / Sign up

Export Citation Format

Share Document