Difference in effects of electro-acupuncture and morphine on thalamic-evoked responses in ventrobasal complex and the posterior nuclear group after tooth pulp stimulation in the rat

1980 ◽  
Vol 25 (10) ◽  
pp. 697-699 ◽  
Author(s):  
A. Iriki ◽  
K. Toda
Keyword(s):  
Tooth Pulp ◽  
Evoked Responses ◽  
Ventrobasal Complex ◽  
Nuclear Group

Wind-up of tooth pulp-evoked responses and its suppression in rat trigeminal caudal neurons

1992 ◽  
Vol 29 (6) ◽  
pp. 883-889 ◽  
Author(s):  
Michiko Hamba ◽  
Hisashi Hisamitsu ◽  
Masuo Muro
Keyword(s):  
Tooth Pulp ◽  
Evoked Responses

Tooth Pulp– and Facial Hair Mechanoreceptor–evoked Responses of Trigeminal Sensory Neurons Are Attenuated during Ketamine Anesthesia 

1999 ◽  
Vol 91 (4) ◽  
pp. 1025-1025 ◽  
Author(s):  
Brian E. Cairns ◽  
Shelly A. McErlane ◽  
Miguel C. Fragoso ◽  
Peter J. Soja
Keyword(s):  
Sensory Neurons ◽  
Time Course ◽  
Afferent Fiber ◽  
Small Diameter ◽  
Tooth Pulp ◽  
Evoked Responses ◽  
Neuronal Responses ◽  
Facial Hair ◽  
Somatosensory Information ◽  
Ketamine Anesthesia

Background Evidence exists that ketamine, administered systemically using a dose required for inducing a state of anesthesia, may antagonize nociceptive but not innocuous input to lumbar dorsal horn neurons. However, it is unclear whether ketamine exerts this selective action on sensory inputs to trigeminal sensory neurons. The current study was undertaken to compare the responses evoked in trigeminal sensory neurons by electrical stimuli applied to the tooth pulp versus air-puff stimuli applied to facial hair mechanoreceptors (FHMs) during quiet wakefulness versus ketamine anesthesia. Methods Accordingly, responses of rostral trigeminal sensory nuclear complex (TSNC) and trigeminothalamic tract neurons evoked by tooth pulp (a source of small-diameter fiber input) and FHMs (a source of larger-diameter fiber input) were recorded extracellularly from chronically instrumented cats before, during, and after recovery from the anesthetic state induced by a single (2.2 mg/kg) intravenous injection of ketamine. Results Overall, tooth pulp-evoked responses of TSNC neurons were maximally suppressed by 50% within 5 min after the intravenous administration of ketamine. Ketamine also suppressed the FHM-evoked responses of TSNC and trigeminothalamic neurons by 45%. The time course of ketamine's suppressive action was equivalent for tooth pulp- and FHM-evoked responses. However, the recovery of tooth pulp-evoked TSNC neuronal responses at suprathreshold intensities was markedly prolonged compared with neuronal responses driven by threshold stimuli or FHM. Conclusions These electrophysiologic results in the chronically instrumented cat preparation indicate that a nonselective suppression of orofacial somatosensory information occurs during ketamine anesthesia. The prolonged recovery of suprathreshold responses of TSNC neurons mediated by small-diameter afferent fiber input may partly underlie the analgesic action of ketamine that is clinically relevant at subanesthetic doses.

Convergence of Afferents from Superior Sagittal Sinus and Tooth Pulp on Cells in the Thalamus of The Cat

Cephalalgia ◽  
1995 ◽  
Vol 15 (3) ◽  
pp. 191-199 ◽  
Author(s):  
H Angus-Leppan ◽  
B Olausson ◽  
P Boers ◽  
GA Lambert
Keyword(s):  
Spinal Cord ◽  
Superior Sagittal Sinus ◽  
Cervical Spinal Cord ◽  
Receptive Fields ◽  
Tooth Pulp ◽  
Intralaminar Nuclei ◽  
Sagittal Sinus ◽  
Ventrobasal Complex ◽  
Stimulation Of

We have previously shown convergence of craniovascular and tooth pulp afferents in the cervical spinal cord of cats. This study looked for similar convergence in the thalamus. Fifty-four thalamic cells with input from tooth pulp, superior sagittal sinus, or both, were identified. Twenty-nine cells with tooth pulp and superior sagittal sinus input were located in the ventrobasal complex or the intralaminar nuclei. Most of these 29 cells were also excited by cooling the contralateral tooth pulp, and 21 had receptive fields on the contralateral face or forelimb. Twenty cells excited by stimulation of superior sagittal sinus, and not tooth pulp, were found in several nuclei. The 5 cells excited by stimulation of tooth pulp, but not sagittal sinus, were restricted to the ventrobasal complex. The data confirm convergence from sagittal sinus, tooth pulp, and skin in the thalamus of anaesthetized cats.

Sign in / Sign up

Export Citation Format

Share Document