Inhibitory effects of intrathecally administered interleukin-1beta on carrageenan-induced hyperalgesia and spinal c-Fos expression in rats.
The present study investigated the effects of interleukin-1beta (IL-1beta) injected intrathecally (i.t.) on carrageenan-induced thermal hyperalgesia and spinal c-Fos expression. The paw withdrawal latency (PWL) by the thermal stimulus was taken as an index of the thermal hyperalgesia of rats. I.t. injection of 10 ng IL-1beta significantly increased the PWL of the carrageenan-injected paw. Expression of c-Fos induced by intraplantar (i.pl.) injection of carrageenan was examined in the spinal cord with immunohistochemical methods. Three hours after i.pl. injection of carrageenan, the number of c-Fos-like immunoreactive (c-Fos-LI) neurons was significantly increased in laminae I-II, III-IV and V-VI of the ipsilateral spinal cord at L4-5 with the higher density in laminae I-II and V-VI. I.t. pre-injected IL-1beta significantly decreased the number of carrageenan-induced c-Fos-LI neurons in laminae I-II in the ipsilateral spinal cord and also inhibited the hyperalgesia induced by i.pl. carrageenan. These results suggested that i.t. injection of IL-1beta suppressed the central nociceptive input into laminae I-II and produced an antinociceptive effect.
Ji
Guang-Chen
GC
Department of Neurobiology, State Key Laboratory of Medical Neurobiology, Medical Center of Fudan University (The Former Shanghai Medical University), P.O. Box 291, 138 Yi-Xue-Yuan Road, 200032, Shanghai, China.
Zhang
Yu-Qiu
YQ
Ma
Fei
F
Cao
Xiao-Ding
XD
Wu
Gen-Cheng
GC
D000344:Afferent Pathways / Q000187:drug effects* / Q000378:metabolism; D000700:Analgesics / Q000494:pharmacology; D000818:Animals; D015415:Biomarkers; D002351:Carrageenan / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects / Q000502:physiology; D006930:Hyperalgesia / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D007249:Inflammation / Q000139:chemically induced / Q000188:drug therapy / Q000503:physiopathology; D007278:Injections, Spinal; D007375:Interleukin-1 / Q000494:pharmacology*; D008297:Male; D009433:Neural Inhibition / Q000187:drug effects* / Q000502:physiology; D009437:Neuralgia / Q000188:drug therapy* / Q000378:metabolism / Q000503:physiopathology; D009619:Nociceptors / Q000187:drug effects* / Q000378:metabolism; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D010523:Peripheral Nervous System Diseases / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D020671:Posterior Horn Cells / Q000187:drug effects* / Q000378:metabolism; D016760:Proto-Oncogene Proteins c-fos / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D016896:Treatment Outcome
D000700:Analgesics; D015415:Biomarkers; D007375:Interleukin-1; D016760:Proto-Oncogene Proteins c-fos; D002351:Carrageenan