The Change of Neuropathic Pain and Pain Related Gene Expression following Exposure to Chronic Smoking.
10.4097/kjae.2007.53.3.374
- Author:
Hyeon Jeong LEE
1
;
Sang Wook SHIN
;
Woo Seong YANG
;
Seung Hoon BAEK
;
Cheul Hong KIM
;
Hae Kyu KIM
;
Seong Wan BAIK
Author Information
1. Department of Anesthesia and Pain Medicine, Pusan National University Hospital, Korea. shinsw@pusan.ac.kr
- Publication Type:Original Article
- Keywords:
brain derived neurotropic factor;
c-fos;
neuropathic pain;
smoking
- MeSH:
Acetone;
Analgesia;
Animals;
Anxiety;
Brain-Derived Neurotrophic Factor;
Gene Expression*;
Hyperalgesia;
Ligation;
Neuralgia*;
Rats;
Rats, Sprague-Dawley;
Real-Time Polymerase Chain Reaction;
Smoke*;
Smoking*;
Spinal Cord;
Spinal Nerves;
Tobacco Products
- From:Korean Journal of Anesthesiology
2007;53(3):374-381
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: Several studies have reported reduced pain and anxiety in smokers, and considerable evidence shows that smoking induces analgesia, which is thought to be nicotine-mediated. We investigated if smoking could reduce the development of neuropathic pain and nociceptive transmission in the spinal cord. METHODS: Sprague Dawley rats weighing 130-150 g were used for this experiment. The Animals were divided into two groups: the smoking group (S group) was exposed to cigarette smoking for 5 hours per day for 6 weeks at self-made smoking chamber: the control group (C group) was exposed to room air. After a 4-week exposure period, neuropathic pain was induced by left L5 spinal nerve ligation (SNL). Mechanical threshold and withdrawal response to 100% acetone were measured throughout the experiment. The changes in the expression of the c-fos and BDNF genes in the spinal cord were compared using real time PCR. RESULTS: Mechanical allodynia was induced after SNL in both groups, but no significant difference was observed between two groups. Cold allodynia after SNL was significantly less in S group than C group. In S group, the expression of c-fos was decreased at 5th day, but that of BDNF expression was significantly elevated at 5th day after SNL compared to C group. CONCLUSIONS: Chronic exposure to cigarette smoke reduced the cold allodynia in neuropathic rats. The decreased expression of c-fos and elevated expression of BDNF in the spinal cord after SNL may contribute to antinociception.
