Behavioral and Cellular Neuroscience, Department of Psychology, Texas A&M University, College Station, TX 77843, USA.
J Psychopharmacol. 2010 Sep;24(9):1411-7. doi: 10.1177/0269881109106976. Epub 2009 Nov 25.
Drug withdrawal is suggested to play a role in precipitating mood disorders in individuals with familial predisposition. Age-related differences in affective responses to withdrawal might explain the increased risk of mental illnesses when drug use begins during adolescence. Recently we observed that, in contrast to adult male mice, adolescent males exhibited a decrease in immobility in the forced swim test on the third day of withdrawal, as compared with controls. Thus, the present study examined forced swim test behaviors of adolescent female mice during opioid withdrawal. Similar to the male study, adolescent female mice were injected with two morphine regimens which differed in dosage. Three and nine days following discontinuation of morphine administration, forced swim test immobility time and locomotion were evaluated. In contrast to males, which exhibited a decrease in immobility, no significant differences in immobility were observed in female adolescents undergoing withdrawal as compared with saline-injected controls. This sex difference in forced swim test behaviors was not due to changes in overall motor activity, since differences in locomotion were not observed in either male or female adolescent mice. Thus, this study demonstrates sex differences in forced swim test behavior during opioid withdrawal. Forced swim test behaviors are classically used to evaluate mood in rodents, thus this study suggests that opioid withdrawal might affect mood differentially across sexes.
药物戒断被认为在具有家族易感性的个体中诱发情绪障碍起作用。与药物使用开始于青春期相关的与年龄相关的情感反应差异可能解释了当药物使用开始于青春期时精神疾病风险增加的原因。最近，我们观察到，与成年雄性小鼠相比，与对照组相比，在戒断的第三天，青春期雄性小鼠在强迫游泳试验中的不动时间减少。因此，本研究检查了青春期雌性小鼠在阿片类药物戒断期间的强迫游泳试验行为。与雄性研究相似，青春期雌性小鼠接受了两种不同剂量的吗啡方案注射。在停止吗啡给药后 3 天和 9 天，评估了强迫游泳试验的不动时间和运动。与表现出不动时间减少的雄性不同，与接受生理盐水注射的对照组相比，经历戒断的雌性青春期小鼠的不动时间没有明显差异。这种在强迫游泳试验行为中的性别差异不是由于总体运动活性的变化引起的，因为在雄性或雌性青春期小鼠中均未观察到运动差异。因此，这项研究表明在阿片类药物戒断期间，强迫游泳试验行为存在性别差异。强迫游泳试验行为通常用于评估啮齿动物的情绪，因此这项研究表明，阿片类药物戒断可能会以不同的方式影响两性的情绪。
