Abstract
Fangchinoline (FAN), a non-specific calcium antagonist, is a major alkaloidal component of the creeper Stephania tetrandra S. Moore (or fenfangji). It has been shown to possess antagonistic activity on morphine-induced antinociception in mice. This study was undertaken to assess the antagonistic mechanism. The results demonstrated that FAN (IP) attenuated morphine (SC)-induced antinociception in a dose-dependent manner with significant effect at doses of 30 and 60mg/kg body wt. (IP) in the tail-flick test but not the tail-pinch tests, carried out in mice. This antagonism was abolished by pretreatment with a serotonin precursor, 5-hydroxytryptophan (5-HTP, IP), but not by pretreatment with a noradrenaline precursor, L-dihydroxyphenylalanine (L-DOPA, IP) in the tail-flick test. On the other hand, the development of morphine-induced analgesic tolerance was not prevented by FAN. These results suggest that the serotonergic pathway may be involved in the antagonism of morphine-induced antinociception by FAN and, in agreement with other reports, also indicates the possible dissociation of the morphine analgesic effect from its tolerance-development mechanism.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.