cDNA microarray analysis of the differential gene expression in the neuropathic pain and electroacupuncture treatment models.
Partial nerve injury is the main cause of neuropathic pain disorders in humans. Acupuncture has long been used to relieve pain. It is known to relieve pain by controlling the activities of the autonomic nervous system. Although the mechanism of neuropathic pain and analgesic effects of electroacupuncture (EA) have been studied in a rat model system, its detailed mechanism at the molecular level remains unclear. To identify genes that might serve as either markers or explain these distinct biological functions, a cDNA microarray analysis was used to compare the expression of 8,400 genes among three sample groups. Messenger RNAs that were pooled from the spinal nerves of 7 normal, 7 neuropathic pain, and 7 EA treatment rat models were compared. Sixty-eight genes were differentially expressed more than 2-fold in the neuropathic rat model when compared to the normal, and restored to the normal expression level after the EA treatment. These genes are involved in a number of biological processes, including the signal transduction, gene expression, and nociceptive pathways. Confirmation of the differential gene expression was performed by a dotblot analysis. Dot-blotting results showed that the opioid receptor sigma was among those genes. This indicates that opioid-signaling events are involved in neuropathic pain and the analgesic effects of EA. The potential application of these data include the identification and characterization of signaling pathways that are involved in the EA treatment, studies on the role of the opioid receptor in neuropathic pain, and further exploration on the role of selected identified genes in animal models.
Ko
Jesang
J
Asan Institute for Life Sciences, University of Ulsan College of Medicine 138-736, Korea. jesangko@amc.seoul.kr
Na
Doe Sun
DS
Lee
Young Han
YH
Shin
Soon Young
SY
Kim
Ji Hoon
JH
Hwang
Byung Gil
BG
Min
Byung-Il
BI
Park
Dong Suk
DS
D000818:Animals; D004195:Disease Models, Animal; D015671:Electroacupuncture; D020869:Gene Expression Profiling; D008297:Male; D009437:Neuralgia / Q000235:genetics* / Q000503:physiopathology / Q000628:therapy*; D020411:Oligonucleotide Array Sequence Analysis; D010147:Pain Measurement; D051381:Rats; D017207:Rats, Sprague-Dawley; D017480:Receptors, sigma / Q000235:genetics / Q000502:physiology; D015398:Signal Transduction; D013127:Spinal Nerves / Q000293:injuries
D017480:Receptors, sigma