The Gene Expression of Dynorphin, Enkephalin, c-Fos in the Neuropathic Rat

Autor: Sug Hwa Yoon, Hye Ja Kim, Won Jae Hwang, Byung Doo Hwang, Sae Jin Choi, Won Hyung Lee, Soo Chang Son, Yong Sup Shin, Kyu Lim, Neung Hee Han
Rok vydání: 1996
Předmět:
Zdroj: Korean Journal of Anesthesiology. 31:293
ISSN: 0302-5780
DOI: 10.4097/kjae.1996.31.3.293
Popis: Background: We studied the time course of gene expression of dynorphin, enkephalin, c-fos, and the changes of allodynia, and the effect of chemical sympathectomy on the gene expression and allodynia in neuropathic rat. Methods: In two groups of rat (Sprague-Dawley), the left L5 and L6 spinal nerves were tight ligated. In gene expression group (N=25), behavioral tests for mechanical allodynia and cold allodynia were perfomed for the next two weeks. After the test of allodynia, the expression of dynorphin, enkephalin, c-fos were assessed by Northern blot hybridization. In chemical sympathectomy group (N=16), after chemical sympathectomy (guanethidine 70 mg/kg intraperitoneally, from postoperative 7 days to 9 days), the changes of allodynia and the gene expression of enkephalin, c-fos were tested. Results: Mechanical allodynia and cold allodynia was developed on the postoperative 3, 5, 7, 14 days. Preprodynorphin mRNA expression was reached peak level at the postoperative 8 hrs, sustained increase by the postoperative 3 days, but preproenkephalin mRNA expression increased slightly after operation. c-Fos mRNA expression was increased immediately at the postoperative 30 min, 1 hr, returned to normal level thereafter, and increased again on the postoperative 3, 5, 7 days that neuropathic pain was developed. Mechanical allodynia and cold allodynia were decreased by chemical sympathectomy. The increased c-fos mRNA expression and pain at postoperative 7 days was reduced by chemical sympathectomy. Conclusion: These results suggest that the transient gene expression of dynorphin and c-fos after tight ligation of L5 and L6 spinal nerves induces the development neuropathic pain, and late c-fos expression is related to neuropathic pain. (Korean J Anesthesiol 1996; 31: 293-303)
Databáze: OpenAIRE