Mateos-García A, Roger-Sánchez C, Rodriguez-Arias M, Miñarro J, Aguilar M A, Manzanedo C, Arenas M C
Unidad de investigación Psicobiología de las Drogodependencias, Departamento de Psicobiología, Facultad de Psicología, Universitat de València, Avda. Blasco Ibañez, 21, 46010, Valencia, Spain.
Psychopharmacology (Berl). 2015 Jan;232(1):101-13. doi: 10.1007/s00213-014-3642-y. Epub 2014 Jun 8.
Exposure to drugs during adolescence can induce alterations in the central nervous system. The novelty-seeking personality trait influences differences observed among individuals exposed to drugs of abuse.
Long-term effects of intensive pre-treatment with cocaine during adolescence or adulthood were evaluated in High- and Low-Novelty Seeker (HNS and LNS) mice. It was hypothesized that a cocaine binge during adolescence would increase sensitivity to the rewarding effects of cocaine and MDMA, especially in HNS animals, and modify the spontaneous behaviour of adult animals.
Adolescent (PND 33) and adult (PND 60) mice were identified as HNS or LNS according to their performance in the hole-board test. Subsequently, they received pre-treatment with cocaine (three injections per day of an increasing dose for 10 days) or saline. Three weeks later, the mice performed the hole-board, elevated plus maze, spontaneous locomotor activity and cocaine- (1 mg/kg) or MDMA- (1.25 mg/kg) induced conditioning place preference (CPP) tests. In another set of mice, the effects of pre-treatment of cocaine during adulthood on MDMA- or cocaine-induced CPP were also evaluated 3 weeks later.
Only HNS mice treated with cocaine during adolescence acquired MDMA- or cocaine-induced CPP in adulthood. Moreover, pre-exposure to cocaine during adolescence caused subsequent behavioural alterations, including reduced exploratory behaviour and increased locomotor reactivity.
Cocaine binge administration during adolescence induces a higher sensitivity to the rewarding effects of MDMA and cocaine in HNS mice in adulthood. This may explain the greater vulnerability often seen among individuals exposed early in life to drugs of abuse.
青春期接触药物可诱发中枢神经系统的改变。寻求新奇的人格特质会影响在接触滥用药物的个体中观察到的差异。
在高新奇寻求者（HNS）和低新奇寻求者（LNS）小鼠中评估青春期或成年期高强度可卡因预处理的长期影响。据推测，青春期的可卡因狂饮会增加对可卡因和摇头丸奖赏效应的敏感性，尤其是在HNS动物中，并改变成年动物的自发行为。
根据其在洞板试验中的表现，将青春期（出生后第33天）和成年（出生后第60天）小鼠鉴定为HNS或LNS。随后，它们接受可卡因预处理（每天注射三次递增剂量，持续10天）或生理盐水。三周后，小鼠进行洞板试验、高架十字迷宫试验、自发运动活动试验以及可卡因（1mg/kg）或摇头丸（1.25mg/kg）诱导的条件性位置偏爱（CPP）试验。在另一组小鼠中，三周后还评估了成年期可卡因预处理对摇头丸或可卡因诱导的CPP的影响。
只有青春期接受可卡因治疗的HNS小鼠在成年期获得了摇头丸或可卡因诱导的CPP。此外，青春期预先接触可卡因会导致随后的行为改变，包括探索行为减少和运动反应性增加。
青春期可卡因狂饮给药会使成年期HNS小鼠对摇头丸和可卡因的奖赏效应产生更高的敏感性。这可能解释了早年接触滥用药物的个体中常见的更高易感性。
