Effect of CGRP receptor antagonist CGRP8-37 on nociceptive response, NOS expression and NO content in the dorsal horn of spinal cord during formalin-induced inflammatory pain in rats.
- Author:
Tong-nan LI
1
;
Qing-jun LI
;
Wen-bin LI
;
Xiao-cai SUN
;
Shu-qin LI
Author Information
- Publication Type:Journal Article
- MeSH: Animals; Calcitonin Gene-Related Peptide; pharmacology; Formaldehyde; adverse effects; Nitric Oxide; metabolism; Nitric Oxide Synthase; metabolism; Pain; chemically induced; metabolism; Peptide Fragments; pharmacology; Rats; Rats, Sprague-Dawley; Receptors, Calcitonin Gene-Related Peptide; antagonists & inhibitors; Spinal Cord; drug effects; metabolism
- From: Chinese Journal of Applied Physiology 2004;20(3):291-295
- CountryChina
- Language:Chinese
-
Abstract:
AIMTo study the effect of CGRP receptor antagonist CGRP8-37 on nociceptive response and expression of nitric oxide synthase (NOS) and content of nitric oxide (NO) in the dorsal horn of the spinal cord of rats during formalin-induced inflammatory pain.
METHODSUsing formalin injection into right hind paw induced inflammatory pain. Counting the times of flinching reflex was used to observe the degree of spontaneous pain. NADPH-d histochemistry was used to observe the changes of NOS expression. The content of NO was observed by measuring the contents of nitrate/nitrite (NO3- / NO2-).
RESULTSspontaneous pain behavioral was elicited by formalin injection. The NOS expression and NO content significantly increased in the spinal cord at 24 h after formalin injection. Intrathecal injection of CGRP8-37 could significantly inhibit the response of spontaneous pain and the increases of NOS expression and NO content induced by formalin injection.
CONCLUSIONThe activation of CGRP receptors enhances NOS expression and NO production in the dorsal horn of the spinal cord during formalin-induced inflammatory pain.
