@article{APS7484,
author = {Guang-An He and Hui-Min Hou and Xiao-Jun Liu},
title = {Naltrexone microspheres: in vitro release and effect on morphine analgesia in mice},
journal = {Acta Pharmacologica Sinica},
volume = {22},
number = {6},
year = {2016},
keywords = {},
abstract = {Aim: To study in vitro release and in vivo effect of four different types of sustained-release naltrexone microspheres on morphine analgesia.
Methods: Release of naltrexone from four types of biodegradable microspheres was investigated by HPLC. Their antagonist effects on morphine analgesia were observed using mouse hot-plate procedure.
Results: Poly latide-co-glycolide (PLGA) composition had a remarkable effect on naltrexone release from microspheres and its antagonism towards morphine analgesia. Two formulations of PLGA 50:50 formulation released more than 80 % of total naltrexone and lost their antagonism by 8 d. The PLGA 75:25 formulation with 20 % and 30 % drug loadings did not release 95 % of total drug and lose antagonism until 40 d and 30 d, respectively. Increasing the drug loading enhanced naltrexone release from microspheres and seemed to shorten the analgesic antagonistic effect of naltrexone.
Conclusion: Antagonism by naltrexone microspheres towards morphine analgesia correlates well with the drug release in vitro.},
issn = {1745-7254}, url = {http://www.chinaphar.com/article/view/7484}
}