Central analgesic action of calcitonin and its relationship with central monoamine transmitters
Yang, X.L.; Tang, Y.H.; Zhao, X.P.; Wang, S.
Zhongguo Yao Li Xue Bao 13(2): 156-158
1992
ISSN/ISBN: 0253-9756 PMID: 1350881 Document Number: 398997
The analgesic action of calcitonin (0.25 MRC units .cntdot. kg-1) injected into lateral cerebroventricle was investigated in rats. The pain threshold was evaluated by the tail-flick test. The influences of icv naloxone 5 .mu.g/rat, a blocker of opiate receptor, on the analgesic action of calcitonin were observed. The results showed that icv calcitonin produced a significantly analgesic action, which was reversed by naloxone. While the pain threshold was raised by calcitonin, the contents of central monoamines (5-HT, NE, DA) in brain (diencephalon, brain stem) were examined by fluorophotometry, which were increased remarkably. It is suggested that calcitonin-induced analgesia is related to the opiate receptors and the content of 5-HT, NE, and DA in CNS.