Bartoletti M, Gaiardi M, Gubellini C, Bacchi A, Babbini M
Neuropharmacology. 1987 Feb-Mar;26(2-3):115-9. doi: 10.1016/0028-3908(87)90197-3.
The stimulatory effect of morphine on locomotor activity has been shown to be largely modified in rats that have been formerly dependent on this drug. In the present study, the relationship between the chronic dose of morphine and the degree of sensitization to the excitatory effect of opiates was investigated. To this end, four groups of rats were treated daily for 30 days with 1.25, 5, 20 and 80 mg/kg of morphine (i.p.) and challenged with morphine (1.25 and 2.5 mg/kg) or fentanyl (40 and 80 micrograms/kg) 1-4 months after ceasing the treatment. Drug-induced hypermotility in post-dependent rats appeared to be linearly related to the dose of the preceding chronic treatment after test doses of both morphine and fentanyl. The results are discussed in terms of a persistent dose-related modification of the neuronal mechanism subserving the excitatory component of the action of opiates; such a modification might offer a neurobiological basis for the fact that "relapse tendencies" for opiates persist for a long time after withdrawal.
吗啡对运动活性的刺激作用在先前依赖该药物的大鼠中已显示出很大改变。在本研究中，研究了吗啡的慢性剂量与对阿片类药物兴奋作用的敏化程度之间的关系。为此，将四组大鼠每天腹腔注射1.25、5、20和80mg/kg吗啡，持续30天，并在停止治疗1至4个月后用吗啡（1.25和2.5mg/kg）或芬太尼（40和80μg/kg）进行激发试验。在给予吗啡和芬太尼测试剂量后，依赖后大鼠中药物诱导的运动亢进似乎与先前慢性治疗的剂量呈线性相关。根据维持阿片类药物作用兴奋成分的神经元机制的持续剂量相关改变来讨论这些结果；这种改变可能为阿片类药物“复发倾向”在戒断后长时间持续存在这一事实提供神经生物学基础。
