Involvement of microglial activation in the brainstem in experimental dental injury and inflammation.
OBJECTIVE
The purpose of this study was to determine the effect of dental injury and inflammation on microglia in the trigeminal subnucleus caudalis (Vc).


METHODS
Pulp exposure (PX) was performed on the first maxillary molar of 35 rats. Specimens were collected at 1, 3, 7, 14, 21 and 28 days after PX. Teeth were processed for H&E staining and immunohistochemical staining for OX-42, a marker of microgial activation, in the Vc.


RESULTS
We observed that there was a progressive and persistent inflammation in the tooth. At 21-28 days after PX, the inflammation extended out into periodontal ligament. Simultaneously, significant microglial activation was observed which starting at 2 weeks and peaking at 4 weeks.


CONCLUSIONS
Dental injury and inflammation induced microglial activation in the Vc. The results indicate that activation of microglia may be implicated in the central mechanisms of pain that can be associated with dental inflammation.
Fan
Wenguo
W
Department of Oral Anatomy and Physiology, Guanghua School of Stomatology, Sun Yat-sen University, Guangzhou 510080, China.
Huang
Fang
F
Zhu
Xiao
X
Dong
Weiguo
W
Gao
Zhixiong
Z
Li
Dongpei
D
He
Hongwen
H
D000818:Animals; D003789:Dental Pulp Exposure / Q000503:physiopathology*; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D007124:Immunoenzyme Techniques; D008297:Male; D017628:Microglia / Q000502:physiology*; D058748:Pain Perception / Q000502:physiology*; D011671:Pulpitis / Q000503:physiopathology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D018677:Tooth Injuries / Q000503:physiopathology; D014278:Trigeminal Nuclei / Q000502:physiology*
D005904:Glial Fibrillary Acidic Protein