Martins R C S, Andersen M L, Shih M C, Tufik S
Departamento de Psicobiologia, Escola Paulista de Medicina, Universidade Federal de São Paulo, São Paulo, SP, Brasil.
Braz J Med Biol Res. 2008 Jan;41(1):68-77. doi: 10.1590/s0100-879x2008000100011.
Sleep loss is both common and critically relevant to our society and might lead to the abuse of psychostimulants such as amphetamines, cocaine and modafinil. Since psychoactive substance abuse often occurs within a scenario of sleep deficit, the purpose of this investigation was to compare the sleep patterns of rats challenged with cocaine (7 mg/kg, ip), methamphetamine (7 mg/kg, ip), or modafinil (100 mg/kg, ip) subsequent to paradoxical sleep deprivation (PSD) for 96 h. Our results show that, immediately after 96 h of PSD, rats (10 per group) that were injected with a psychostimulant presented lower percentages of paradoxical sleep compared to those injected with saline (P < 0.01). Regarding slow wave sleep (SWS), rats injected with psychostimulants after PSD presented a late rebound (on the second night subsequent to the injection) in the percentage of this phase of sleep when compared to PSD rats injected with saline (P < 0.05). In addition, the current study has produced evidence of the characteristic effect of each drug on sleep architecture. Home cage control rats injected with modafinil and methamphetamine showed a reduction in SWS compared with the saline group. Methamphetamine affected sleep patterns most, since it significantly reduced paradoxical sleep, SWS and sleep efficiency before and after PSD compared to control (P < 0.05). Cocaine was the psychostimulant causing the least changes in sleep pattern in relation to those observed after saline injection. Therefore, our results suggest that abuse of these psychostimulants in a PSD paradigm aggravates their impact on sleep patterns.
睡眠不足在我们的社会中既常见又至关重要，并且可能导致对苯丙胺、可卡因和莫达非尼等精神兴奋剂的滥用。由于精神活性物质滥用通常发生在睡眠不足的情况下，本研究的目的是比较在进行96小时的异相睡眠剥夺（PSD）后，接受可卡因（7毫克/千克，腹腔注射）、甲基苯丙胺（7毫克/千克，腹腔注射）或莫达非尼（100毫克/千克，腹腔注射）刺激的大鼠的睡眠模式。我们的结果表明，在PSD 96小时后，立即注射精神兴奋剂的大鼠（每组10只）与注射生理盐水的大鼠相比，异相睡眠的百分比更低（P < 0.01）。关于慢波睡眠（SWS），与注射生理盐水的PSD大鼠相比，PSD后注射精神兴奋剂的大鼠在睡眠这一阶段的百分比上出现了延迟反弹（在注射后的第二个晚上）（P < 0.05）。此外，本研究还提供了每种药物对睡眠结构的特征性影响的证据。与生理盐水组相比，注射莫达非尼和甲基苯丙胺的笼养对照大鼠的SWS减少。甲基苯丙胺对睡眠模式的影响最大，因为与对照组相比，它在PSD前后显著降低了异相睡眠、SWS和睡眠效率（P < 0.05）。与注射生理盐水后观察到的情况相比，可卡因是导致睡眠模式变化最小的精神兴奋剂。因此，我们的结果表明，在PSD范式中滥用这些精神兴奋剂会加剧它们对睡眠模式的影响。
