Expression of vesicular glutamate transporters VGLUT1 and VGLUT2 in the rat dental pulp and trigeminal ganglion following inflammation.

Abstract

BACKGROUND:

There is increasing evidence that peripheral glutamate signaling mechanism is involved in the nociceptive transmission during pathological conditions. However, little is known about the glutamate signaling mechanism and related specific type of vesicular glutamate transporter (VGLUT) in the dental pulp following inflammation. To address this issue, we investigated expression and protein levels of VGLUT1 and VGLUT2 in the dental pulp and trigeminal ganglion (TG) following complete Freund's adjuvant (CFA) application to the rat dental pulp by light microscopic immunohistochemistry and Western blot analysis.

RESULTS:

The density of VGLUT2- immunopositive (+) axons in the dental pulp and the number of VGLUT2+ soma in the TG increased significantly in the CFA-treated group, compared to control group. The protein levels of VGLUT2 in the dental pulp and TG were also significantly higher in the CFA-treated group than control group by Western blot analysis. The density of VGLUT1+ axons in the dental pulp and soma in the TG remained unchanged in the CFA-treated group.

CONCLUSIONS:

These findings suggest that glutamate signaling that is mediated by VGLUT2 in the pulpal axons may be enhanced in the inflamed dental pulp, which may contribute to pulpal axon sensitization leading to hyperalgesia following inflammation.

• Authors: Eun Sun Yang, Myoung Uk Jin, Jae Hyun Hong, Yun Sook Kim, So Young Choi, Tae Heon Kim, Yi Sul Cho, Yong Chul Bae
• Journal: PloS one (PLoS One) Vol. 9 Issue 10 Pg. e109723 ( 2014) ISSN: 1932-6203 [Electronic] United States
• PMID: 25290694 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Slc17a6 protein, rat
• Slc17a7 protein, rat
• Vesicular Glutamate Transport Protein 1
• Vesicular Glutamate Transport Protein 2
• Glutamic Acid
• Freund's Adjuvant

Topics

• Animals
• Axons (drug effects, metabolism, pathology)
• Dental Pulp (drug effects, metabolism, physiopathology)
• Freund's Adjuvant (administration & dosage)
• Gene Expression Regulation
• Glutamic Acid (metabolism)
• Hyperalgesia (etiology, genetics, physiopathology)
• Inflammation (chemically induced, complications, genetics, physiopathology)
• Male
• Rats
• Rats, Sprague-Dawley
• Signal Transduction
• Trigeminal Ganglion (drug effects, metabolism, physiopathology)
• Vesicular Glutamate Transport Protein 1 (genetics, metabolism)
• Vesicular Glutamate Transport Protein 2 (genetics, metabolism)