Heinsbroek R P, Feenstra M G, Boon P, Van Haaren F, Van de Poll N E
Behavioral Neuroendocrinology Unit, Netherlands Institute for Brain Research, Amsterdam.
Pharmacol Biochem Behav. 1988 Oct;31(2):499-503. doi: 10.1016/0091-3057(88)90380-2.
Effects of the neurotoxin para-chloroamphetamine (PCA) on sex differences in passive avoidance were studied. Seven days prior to passive avoidance training and testing, male and female rats were injected with PCA (5 mg/kg) or physiological saline (SAL). Treatment effects on brain monoamines levels were evaluated in brains collected shortly after the passive avoidance test. Compared to SAL-treated control groups PCA severely reduced both serotonin (5-HT) and 5-hydroxyindole-acetic acid (5-HIAA) in the frontal cortex of males and females. Levels of dopamine (DA) and homovanillic acid (HVA) in the frontal cortex were not affected. These data are indicative of a strong and selective depression of the central 5-HT activity. PCA- and SAL-treated male and female rats were trained and tested in a two-compartment step-through passive avoidance apparatus. Sex differences in passive avoidance were clearly observed in the SAL-treated control groups; a higher number of males did not enter either compartment within the maximum test duration. After PCA treatment sex differences in passive avoidance were abolished, mainly resulting from an increase in the number of PCA-males reentering. Irrespective of sex or treatment subjects seldom failed to choose the nonshock compartment when entering during the passive avoidance test, indicating that disturbance of memory or learning cannot explain for the present results. Rather, the data are discussed in terms of a sex-specific role of central 5-HT in punishment-induced behavioral suppression.
研究了神经毒素对氯苯丙胺（PCA）对被动回避中性别差异的影响。在被动回避训练和测试前7天，给雄性和雌性大鼠注射PCA（5毫克/千克）或生理盐水（SAL）。在被动回避测试后不久收集的大脑中评估治疗对脑单胺水平的影响。与生理盐水处理的对照组相比，PCA严重降低了雄性和雌性额叶皮质中的血清素（5-HT）和5-羟基吲哚乙酸（5-HIAA）。额叶皮质中的多巴胺（DA）和高香草酸（HVA）水平未受影响。这些数据表明中枢5-HT活性受到强烈且选择性的抑制。用PCA和生理盐水处理的雄性和雌性大鼠在两室穿梭式被动回避装置中进行训练和测试。在生理盐水处理的对照组中清楚地观察到被动回避中的性别差异；在最大测试持续时间内，更多的雄性没有进入任何一个隔室。PCA处理后，被动回避中的性别差异消失，主要是由于重新进入的PCA处理的雄性数量增加。无论性别或处理如何，在被动回避测试期间进入时，受试者很少不选择无电击隔室，这表明记忆或学习障碍不能解释目前的结果。相反，这些数据是根据中枢5-HT在惩罚诱导的行为抑制中的性别特异性作用进行讨论的。
