Experimental Brain Research

, Volume 179, Issue 2, pp 181–190

Modulation of neuronal activity in CNS pain pathways following propofol administration in rats: Fos and EEG analysis

Authors

  • Ieko Kubota
    • Department of AnesthesiologyNihon University School of Dentistry
  • Yoshiyuki Tsuboi
    • Department of PhysiologyNihon University School of Dentistry
    • Division of Functional Morphology, Dental Research CenterNihon University School of Dentistry
  • Emi Shoda
    • Department of AnesthesiologyNihon University School of Dentistry
  • Masahiro Kondo
    • Department of PhysiologyNihon University School of Dentistry
    • Division of Functional Morphology, Dental Research CenterNihon University School of Dentistry
  • Yuji Masuda
    • Division of Oral and Maxillofacial Biology, Institute for Oral ScienceMatsumoto Dental University
  • Junichi Kitagawa
    • Department of Physiology, School of Life Dentistry at TokyoNippon Dental University
  • Yoshiyuki Oi
    • Department of AnesthesiologyNihon University School of Dentistry
    • Department of PhysiologyNihon University School of Dentistry
    • Division of Functional Morphology, Dental Research CenterNihon University School of Dentistry
    • Division of Applied System Neuroscience Advanced Medical Research CenterNihon University Graduate School of Medical Science
Research Article

DOI: 10.1007/s00221-006-0779-x

Cite this article as:
Kubota, I., Tsuboi, Y., Shoda, E. et al. Exp Brain Res (2007) 179: 181. doi:10.1007/s00221-006-0779-x

Abstract

We studied Fos expression in the central nociceptive pathways at different sedative levels in order to clarify the central mechanism of propofol’s nociceptive action. Sprague–Dawley rats received propofol (PRO) or pentobarbital (PEN) and were divided into two groups with different doses of drug administration (light and deep sedative levels) based on the electroencephalogram analysis. Rats at each sedative level received heat stimulation to their face and Fos immunohistochemistry was performed at various brain sites. We also infused lidocaine into the jugular vein to test whether PRO directly activated nociceptors distributed in the vein. Fos expression in two major ascending pain pathways (lateral and medial systems) and descending modulatory system were precisely analyzed following intravenous (i.v.) administration of PRO or PEN. Many Fos protein-like immunoreactive (Fos protein-LI) cells were expressed in the trigeminal spinal nucleus caudalis (Vc), parabrachial nucleus, parafascicular nucleus, a wide area of the primary somatosensory cortex, anterior cingulate cortex, amygdala, periaqueductal gray, solitary tract nucleus, and lateral hypothalamus following heating of the face during PRO or PEN infusion. The number of Fos protein-LI cells was significantly greater in many Central nervous system regions during PRO infusion compared with PEN. Fos expression was significantly greater in the Vc and Periaqueductal gray following greater amount of PRO infusions compared, whereas they were significantly smaller in the Vc in the rats with PEN infusion. The Fos expression was significantly depressed following i.v. infusion of lidocaine before PRO administration. The present findings suggest that PRO is involved in the enhancement of Vc activity through direct activation of the primary afferent fibers innervating veins, resulting in pain induction during infusion.

Keywords

Sedation Nociception Trigeminal Rat Propofol

Abbreviations

ACC

Anterior cingulate cortex

Aq

Aqueduct

BLA

Basolateral amygdaroid nucleus

CNS

Central nervous system

CeA

Central nucleus of amygdala

EEG

Electroencephalograph

HP

Hypothalamus

INS

Insular

LPBN

Lateral parabrachial nucleus

Me5

Mesencephalic nucleus

PAG

Periaqueductal gray

PEN

Pentobarbital

PF

Parafascicular thalamic nucleus

PRO

Propofol

Py

Pyramis

RVM

Rostral ventromedial medulla

SI

Primary somatosensory cortex

SC

Superior colliculus

SN

Substantia nigra

Sm

Thalamic nucleus submedius

STN

Solitary tract nucleus

V3

3rd ventricle

VBc

Ventrobasal thalamic complex

Vc

Trigeminal spinal nucleus caudalis

VLO

Ventrolateral orbital cortex

cc

Central canal

scp

Superior cerebellar peduncle

Copyright information

© Springer-Verlag 2006