Effect of Acute and Chronic Administration of Methimazole on Morphine Withdrawal Signs in Adult Male Mice

Opioid receptors change in CNS by anti thyroid hormones drugs. In this study effect of acute and chronic methimazole (aMTZ and cMTZ) administration on morphine withdrawal were investigated. In this experimental study adult male mice divided into control and experimental groups receiving aMTZ or cMTZ. All groups were addicted to morphine and morphine withdrawal was induced by naloxone and jumping, rearing and climbing signs were evaluated. Acute MTZ and chronic MTZ increased the climbing and jumping (p< 0.01, p< 0.001). cMTZ was more potent than the acute one. MTZ probably influences an opioid abstinence directly and/or indirectly through decrement of thyroid hormones.