Bonate P L, Swann A, Silverman P B
University of Texas Health Sciences Center at Houston, Department of Psychiatry and Behavioral Sciences, 77030, USA.
Life Sci. 1997;60(1):PL1-7. doi: 10.1016/s0024-3205(96)00591-7.
We investigated the effect of amphetamine pretreatment on the locomotor response to subsequent cocaine challenge. Rats were administered either 0.75 mg/kg amphetamine in a testing environment and saline in their home cage, saline in the testing environment and 0.75 mg/kg amphetamine in their home cage, or saline in both the testing environment and home cage. After 5 pairings of drug to environment, conditioning was tested by administration of a saline injection. Both amphetamine treated groups exhibited increased locomotion in response to saline injection. After the eighth session of the pairing regimen, all animals were administered 5 mg/kg cocaine in the test environment and their behavior measured for 30 min. Sensitization to cocaine was observed only in rats with previous amphetamine exposure in the testing environment. There was no difference between groups in whole brain, striatal, or plasma levels of cocaine. The data support the hypothesis that sensitization is independent of brain cocaine levels.
我们研究了苯丙胺预处理对随后给予可卡因激发后运动反应的影响。将大鼠分为三组，分别在测试环境中给予0.75mg/kg苯丙胺而在其饲养笼中给予生理盐水、在测试环境中给予生理盐水而在其饲养笼中给予0.75mg/kg苯丙胺、在测试环境和饲养笼中均给予生理盐水。在药物与环境进行5次配对后，通过注射生理盐水来测试条件反射。两个接受苯丙胺处理的组在注射生理盐水后均表现出运动增加。在配对方案的第八次实验后，所有动物在测试环境中给予5mg/kg可卡因，并测量其30分钟的行为。仅在测试环境中先前接触过苯丙胺的大鼠中观察到对可卡因的敏化作用。各组之间全脑、纹状体或血浆中的可卡因水平没有差异。这些数据支持了敏化作用与脑内可卡因水平无关的假说。
