Involvement of calcitonin gene-related peptide and its receptor in anti-nociception in the periaqueductal grey of rats.
The present study investigated the role of calcitonin gene-related peptide (CGRP) in the modulation of nociception in periaqueductal grey (PAG) of rats. Hindpaw withdrawal latencies (HWLs) were tested by hot-plate and Randall Selitto tests. The HWLs to thermal and mechanical stimulation increased significantly after intra-PAG administration of 0.26 or 0.13 nmol of CGRP, but not 0.026 nmol of CGRP. The anti-nociceptive effects induced by CGRP were significantly blocked by intra-PAG administration of 0.026 or 0.26 nmol of the CGRP1 receptor antagonist CGRP8-37. Furthermore, administration of CGRP into the decussation of superior cerebellar peduncle, out of PAG, did not elicit anti-nociceptive effects during 60 min after the injection. The results demonstrated that CGRP plays an important role in anti-nociception in PAG of rats, and CGRP1 receptor is involved in the CGRP-induced anti-nociception.
Yu
Long-Chuan
LC
Laboratory of Neurobiology, College of Life Sciences, National Laboratory of Biomembrane and Membrane Biotechnology, Peking University, Beijing 100871, China. yulc@pku.edu.cn
Weng
Xing-He
XH
Wang
Jing-Wen
JW
Lundeberg
Thomas
T
D000344:Afferent Pathways / Q000187:drug effects / Q000378:metabolism*; D000818:Animals; D015740:Calcitonin Gene-Related Peptide / Q000378:metabolism* / Q000494:pharmacology; D006614:Hindlimb / Q000294:innervation; D008297:Male; D009619:Nociceptors / Q000187:drug effects / Q000378:metabolism*; D010146:Pain / Q000188:drug therapy / Q000378:metabolism* / Q000503:physiopathology; D010147:Pain Measurement / Q000187:drug effects; D017288:Pain Threshold / Q000187:drug effects / Q000502:physiology; D010446:Peptide Fragments / Q000494:pharmacology; D010487:Periaqueductal Gray / Q000187:drug effects / Q000378:metabolism*; D010812:Physical Stimulation; D051381:Rats; D017207:Rats, Sprague-Dawley; D011930:Reaction Time / Q000187:drug effects / Q000502:physiology; D018015:Receptors, Calcitonin Gene-Related Peptide / Q000187:drug effects / Q000378:metabolism*
D010446:Peptide Fragments; D018015:Receptors, Calcitonin Gene-Related Peptide; C058636:calcitonin gene-related peptide (8-37); D015740:Calcitonin Gene-Related Peptide