Methadone and morphine have equivalent analgesic but not reward potency in female mice

IF 2.2

Addiction neuroscience Pub Date : 2025-09-24 DOI:10.1016/j.addicn.2025.100238

Akash Shanmugam , Samantha O. Vanderhoof , Michael A. Kelberman , Sergi Ferre , Katharine E. McCann , David Weinshenker

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引用次数: 0

Abstract

Background

Morphine is a potent opioid analgesic but carries high abuse potential. Some evidence indicates that the opioid methadone, used in maintenance therapy for opioid dependence, also provides analgesia with lower misuse liability, but direct behavioral comparisons of morphine and methadone under matched conditions remain limited.

Methods

Dose responses curves for morphine and methadone (0.3–10 mg/kg) were generated in adult female C57BL6/J mice using paradigms to measure reward (conditioned place preference) and analgesia (von Frey and hot plate).

Results

Morphine supported a conditioned place preference at all doses tested, while methadone induced a significant place preference at 1 and 10 mg/kg, but not at 0.3 mg/kg. Both opioids increased mechanical and thermal antinociceptive thresholds only at the highest dose tested (10 mg/kg).

Conclusions

These findings demonstrate that methadone has a lower reward, but similar analgesic potency compared to morphine in female mice.

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美沙酮和吗啡在雌性小鼠中具有相同的镇痛效力，但没有奖励效力

吗啡是一种有效的阿片类镇痛药，但也有很高的滥用潜力。一些证据表明，阿片类药物美沙酮用于阿片类药物依赖的维持治疗，也提供了较低的滥用风险镇痛，但在匹配条件下吗啡和美沙酮的直接行为比较仍然有限。方法以吗啡和美沙酮（0.3 ~ 10 mg/kg）对成年雌性C57BL6/J小鼠的奖励（条件位置偏好）和镇痛（von Frey和热板）测量模式生成吗啡和美沙酮（0.3 ~ 10 mg/kg）的剂量反应曲线。结果吗啡在所有剂量下均支持条件位置偏好，而美沙酮在1和10 mg/kg剂量下诱导位置偏好显著，而在0.3 mg/kg剂量下无明显作用。两种阿片类药物仅在最高剂量（10 mg/kg）时增加机械和热抗痛觉阈值。结论与吗啡相比，美沙酮对雌性小鼠的镇痛效果相似，但对雌性小鼠的奖励较低。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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