Neuron-immune interactions in the sensitized thalamus induced by mustard oil application to rat molar pulp.
We have reported that mustard oil application to the rat dental pulp induces neuronal activation in the thalamus. To address the mechanisms involved in the thalamic changes, we performed neuronal responsiveness recording, immunohistochemistry, and molecular biological analysis. After mustard oil application, neuronal responsiveness was increased in the mediodorsal nucleus. When MK801 (an N-methyl-D-aspartate receptor antagonist) was applied to the mediodorsal nucleus, the enhanced responsiveness was decreased. N-methyl-D-aspartate receptor 2D, glial fibrillary acidic protein, and antigen-presenting cell-related gene mRNAs in the contralateral thalamus were up-regulated at 10 minutes after mustard oil application, but were down-regulated within 10 minutes after the antagonist application. OX6-expressing microglia and glial fibrillary acidic protein-expressing astrocytes did not increase until 60 minutes after mustard oil application. These results suggested that the thalamic neurons play some roles in regulating the glial cell activation in the mediodorsal nucleus via N-methyl-D-aspartate receptor 2D during pulp inflammation-induced central sensitization.
Kawamura
J
J
Pulp Biology and Endodontics, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan.
Kaneko
T
T
Kaneko
M
M
Sunakawa
M
M
Kaneko
R
R
Chokechanachaisakul
U
U
Okiji
T
T
Suda
H
H
D000818:Animals; D000938:Antigen-Presenting Cells / Q000276:immunology; D001253:Astrocytes / Q000276:immunology / Q000502:physiology; D003782:Dental Pulp / Q000187:drug effects* / Q000276:immunology / Q000294:innervation; D016291:Dizocilpine Maleate / Q000494:pharmacology; D004558:Electric Stimulation; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D007150:Immunohistochemistry; D008297:Male; D020645:Mediodorsal Thalamic Nucleus / Q000187:drug effects / Q000502:physiology; D017628:Microglia / Q000276:immunology / Q000502:physiology; D008963:Molar / Q000187:drug effects / Q000276:immunology / Q000294:innervation; D008967:Molecular Biology; D009149:Mustard Plant / Q000009:adverse effects*; D009434:Neural Pathways / Q000276:immunology; D009457:Neuroglia / Q000276:immunology / Q000502:physiology; D015213:Neuroimmunomodulation / Q000276:immunology / Q000502:physiology; D009474:Neurons / Q000276:immunology / Q000502:physiology; D010938:Plant Oils / Q000009:adverse effects*; D011671:Pulpitis / Q000139:chemically induced / Q000276:immunology; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis / Q000037:antagonists & inhibitors; D013788:Thalamus / Q000187:drug effects / Q000276:immunology*
D018691:Excitatory Amino Acid Antagonists; D005904:Glial Fibrillary Acidic Protein; D010938:Plant Oils; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate; C027793:mustard oil