Many adolescents use amphetamines which are the second most common abused illegal drugs. Methamphetamine (Meth), as a potent amphetamine affects attentional functions. However, the most significant factor for susceptibility to Meth is the age of exposure, most studies have examined the effects of Meth after early adolescence stage. The present experiment was aimed to investigate some possible short- and long-term effects of Meth at two distinct points of adolescence stage (early versus late) on 1) locomotor activity in adolescent rats and 2) attentional functions in their adulthood. Rats received Meth (5 mg/kg, i.p., for consecutive 10 days) during early adolescence (postnatal days (PND) 30–39) or late adolescence (PND 50–59). Locomotor activity was assessed after the first and tenth injections. Then, in adulthood, rats were trained and tested on the Five-choice serial reaction time task (5-CSRTT) to display possible attentional impairments. The first Meth administration in early exposed adolescent (EEA) group produced the highest level of activity, compared with the first exposure in late exposed adolescent (LEA) group and tenth administrations in both groups. In adulthood, LEA group significantly delayed learning the 5-CSRTT and exhibited attentional impairments, as demonstrated by significant reduced response accuracy and increased omission errors under pharmacological challenge, compared with control group. The susceptibility to Meth depends on the age of exposure and Meth administration during late adolescence stage may cause prolonged attentional deficits in adulthood.

许多青少年使用苯丙胺，苯丙胺是第二种最常见的滥用违禁药物。甲基苯丙胺（甲基苯丙胺），作为有效的苯丙胺会影响注意力功能。然而，对甲基化的敏感性最重要的因素是暴露的年龄，大多数研究已经检查了青春期早期后甲基化的影响。本实验旨在研究在两个不同的青春期阶段（早期与晚期），甲基冰毒对1）青春期大鼠的运动能力和2）成年期注意力功能的一些短期和长期影响。大鼠在青春期早期（出生后天数（PND）30-39）或青春期晚期（PND 50-59）连续10天接受Meth（5 mg / kg，腹腔注射）。在第一次和第十次注射后评估运动能力。然后，成年后 对大鼠进行了五选择序列反应时间任务（5-CSRTT）的训练和测试，以显示可能的注意力障碍。与早期暴露青少年（LEA）组和两组的第十次施用相比，早期暴露青少年（EEA）组的首次施用甲基苯丙氨酸产生最高水平的活性。与成年组相比，LEA组在成年期显着延迟了5-CSRTT的学习，并表现出注意力障碍，这在药理学挑战下显着降低了应答准确性并增加了漏失错误。对甲基化的敏感性取决于暴露的年龄，在青春期后期施用甲基化可能会导致成年期长时间的注意力缺陷。