Involvement of CGRP and CGRPl receptor in nociception in the basolateral nucleus of amygdala of rats.
The present study was performed to investigate the role of calcitonin gene-related peptide (CGRP) and its receptor in nociception in the basolateral nucleus of amygdala (BLA) of rats. Hindpaw withdrawal latencies (HWLs) to noxious thermal and mechanical stimulations were measured by hot plate and Randall Selitto tests. The HWL to both thermal and mechanical stimulations increased significantly after intra-BLA administration of 1.0 or 2.0 nmol CGRP, but not 0.5 nmol, indicating that CGRP plays an anti-nociceptive role in BLA of rats. The anti-nociceptive effect of 1.0 nmol CGRP was blocked significantly by administration of 1.0 or 2.0 nmol CGRP8-37, a selective antagonist of CGRP1 receptor, which suggests that the anti-nociceptive effect of CGRP is mediated by the CGRP1 receptor. Taken together, the results indicate that both CGRP and CGRP1 receptor play important roles in nociceptive modulation in the BLA of rats.
Li
Ning
N
Weifang Medical University, Weifang 261042, Shandong Province, People's Republic of China. liningmk@yahoo.com.cn
Liang
Jing
J
Fang
Chun-Yan
CY
Han
Hui-Rong
HR
Ma
Mai-Sheng
MS
Zhang
Guang-Xue
GX
D000679:Amygdala / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D001522:Behavior, Animal; D015740:Calcitonin Gene-Related Peptide / Q000037:antagonists & inhibitors / Q000378:metabolism* / Q000494:pharmacology / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D008297:Male; D009619:Nociceptors / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D010146:Pain / Q000188:drug therapy / Q000209:etiology / Q000378:metabolism*; D010147:Pain Measurement / Q000379:methods; D010446:Peptide Fragments / Q000494:pharmacology; D010812:Physical Stimulation / Q000009:adverse effects; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D018015:Receptors, Calcitonin Gene-Related Peptide / Q000378:metabolism*
D010446:Peptide Fragments; D018015:Receptors, Calcitonin Gene-Related Peptide; C058636:calcitonin gene-related peptide (8-37); D015740:Calcitonin Gene-Related Peptide