Haney M, Maccari S, Le Moal M, Simon H, Piazza P V
Laboratoire de Psychobiologie des Comportements Adaptatifs, INSERM U. 259, Université de Bordeaux II, France.
Brain Res. 1995 Nov 6;698(1-2):46-52. doi: 10.1016/0006-8993(95)00788-r.
The effect of social stress on the vulnerability to commence cocaine self-administration was examined in Sprague-Dawley rats repeatedly exposed to aggressive attack by a same-sex opponent. Both sexes were studied, since the factors influencing the acquisition of drug self-administration in females have not been defined. Male and female rats encountered an aggressive male or lactating female opponent on four separate occasions over the course of one week. Control male and female rats were not exposed to attack. All animals were implanted with jugular catheters, and six days later placed into the self-administration box, where a nose-poke in the designated 'active hole' resulted in a 20 microliters injection of cocaine (0.32 mg/kg). Nose-pokes in an 'inactive' hole had no effect. Male and female rats that had experienced social stress self-administered more cocaine than non-defeated controls. The difference between the stressed and non-stressed animals in the number of cocaine injections was not present during the first few days of exposure to cocaine, but became more pronounced over time. Social stress increased the number of responses for cocaine, but did not alter the number of non-specific responses. Sex differences in self-administration were not significant. Therefore, social status appears to be a potent influence in the onset of drug taking behavior in both male and female rats.
在反复遭受同性对手攻击的斯普拉格-道利大鼠中，研究了社会压力对开始可卡因自我给药易感性的影响。对两性都进行了研究，因为影响雌性大鼠药物自我给药习得的因素尚未明确。雄性和雌性大鼠在一周内分四次遇到具有攻击性的雄性或哺乳期雌性对手。对照雄性和雌性大鼠未遭受攻击。所有动物均植入颈静脉导管，六天后放入自我给药箱，在指定的“活动孔”中戳鼻会导致注射20微升可卡因（0.32毫克/千克）。在“非活动”孔中戳鼻则无效果。经历过社会压力的雄性和雌性大鼠比未受挫败的对照大鼠自我给药的可卡因更多。在接触可卡因的最初几天，受压力和未受压力动物之间在可卡因注射次数上没有差异，但随着时间的推移差异变得更加明显。社会压力增加了对可卡因的反应次数，但没有改变非特异性反应的次数。自我给药中的性别差异不显著。因此，社会地位似乎对雄性和雌性大鼠吸毒行为的开始都有强大影响。
