Antiinflammatory action of endocannabinoid palmitoylethanolamide and the synthetic cannabinoid nabilone in a model of acute inflammation in the rat
作者:Silvia Conti、Barbara Costa、Mariapia Colleoni、Daniela Parolaro、Gabriella Giagnoni
DOI:10.1038/sj.bjp.0704466
日期:2002.1
The antiinflammatory activity of synthetic cannabinoid nabilone in the rat model of carrageenan‐induced acute hindpaw inflammation was compared with that of the endocannabinoid palmitoylethanolamide and the nonsteroidal antiinflammatory drug indomethacin.
Preliminary experiments in rats used a tetrad of behavioural tests, specific for tetrahydrocannabinol‐type activity in the CNS. These showed that the oral dose of nabilone 2.5 mg kg−1 had no cannabinoid psychoactivity.
Intraplantar injection of carrageenan (1% w v−1) elicited a time‐dependent increase in paw volume and thermal hyperalgesia.
Nabilone (0.75, 1.5, 2.5 mg kg−1, p.o.), given 1 h before carrageenan, reduced the development of oedema and the associated hyperalgesia in a dose‐related manner. Nabilone 2.5 mg kg−1, palmitoylethanolamide 10 mg kg−1 and indomethacin 5 mg kg−1, given p.o. 1 h before carrageenan, also reduced the inflammatory parameters in a time‐dependent manner.
The selective CB2 cannabinoid receptor antagonist N‐[(1S)‐endo‐1,3,3‐trimethyl bicyclo [2.2.1]heptan‐2‐yl]‐5‐(4‐chloro‐3‐methylphenyl)‐1‐(4‐methylbenzyl)pyrazole‐3 carboxamide} (SR 144528), 3 mg kg−1 p.o. 1 h before nabilone and palmitoylethanolamide, prevented the anti‐oedema and antihyperalgesic effects of the two cannabinoid agonists 3 h after carrageenan.
Our findings show the antiinflammatory effect of nabilone and confirm that of palmitoylethanolamide indicating that these actions are mediated by an uncharacterized CB2‐like cannabinoid receptor.
British Journal of Pharmacology (2002) 135, 181–187; doi:10.1038/sj.bjp.0704466
研究比较了合成大麻素nabilone与内源性大麻素palmitoylethanolamide以及非甾体抗炎药indomethacin在角叉菜胶诱导的大鼠后爪急性炎症模型中的抗炎活性。
初步实验在大鼠中使用了四组特定于四氢大麻酚类中枢神经系统活性的行为测试。结果显示,nabilone的口服剂量为2.5 mg kg−1没有大麻素类的精神活性。
向后爪注射角叉菜胶(1% w v−1)引起爪体积随时间增加和热痛觉过敏。
nabilone(0.75、1.5、2.5 mg kg−1,口服),在角叉菜胶注射前1小时给药,以剂量依赖性方式减轻了水肿及其相关痛觉过敏。nabilone 2.5 mg kg−1、palmitoylethanolamide 10 mg kg−1和indomethacin 5 mg kg−1,在角叉菜胶注射前1小时口服,也以时间依赖性方式减轻了炎症参数。
选择性CB2大麻素受体拮抗剂N-[(1S)-endo-1,3,3-三甲基双环[2.2.1]庚烷-2-基]-5-(4-氯-3-甲基苯基)-1-(4-甲基苄基)吡咯烷-3-甲酰胺}(SR 144528),3 mg kg−1,在nabilone和palmitoylethanolamide给药前1小时口服,阻止了两种大麻素激动剂在角叉菜胶注射3小时后后的抗水肿和抗痛觉过敏作用。
我们的研究结果表明nabilone的抗炎作用,并证实了palmitoylethanolamide的效果,表明这些作用是由一种未表征的CB2样大麻素受体介导的。
British Journal of Pharmacology(2002)135,181–187;doi:10.1038/sj.bjp.0704466