Sex differences in the acquisition and maintenance of cocaine and nicotine self-administration in rats.
Sex differences in the acquisition and maintenance of cocaine and nicotine self-administration in rats.
复制标题
大鼠自我给药可卡因和尼古丁的获取和维持的性别差异。
DOI：
10.1007/s00213-015-4183-8
复制
发表时间：
2016
影响因子：
3.4
通讯作者：
Carroll,MarilynE
中科院分区：
文献类型：
--
作者：
Swalve,Natashia;Smethells,JohnR;Carroll,MarilynE
合理在人类吸毒成瘾中观察到一致的性别差异，女性吸毒量经常超过男性。本研究考察了可卡因和尼古丁这两种广泛使用的兴奋剂在获得和维持自身给药方面的性别差异。方法雌雄大鼠在固定比例1(FR 1)下每天给药(0.4 mg/kg/次)或尼古丁(0.03 mg/kg/次/次)，直到达到获得标准(最多30次)。可卡因的自我给药标准是在2小时内注射≥20，在1小时内注射≥5尼古丁。通过检测符合获得标准的大鼠的百分比、达到标准的会话次数和在维持阶段获得的输液次数来评估性别差异。结果雄性大鼠同时获得可卡因和尼古丁自我管理的百分比显著高于雌性大鼠，并且雄性大鼠在较少的会话中达到获得标准。然而，在满足标准后，在维持生命的前5天，女性自己服用的可卡因比男性多。吸食尼古丁后的尼古丁摄入没有性别差异。结论性别间获得尼古丁的差异可以揭示药物使用的开始是不可或缺的因素，而药物成瘾是经常被忽视的一个阶段。
RationaleConsistent sex differences are observed in human drug addiction, with females often exceeding males on drug intake. However, there is still a need for animal models for some aspects of addiction such as acquisition of drug self-administration and the subsequent development of drug-seeking.ObjectivesThe present study examined sex differences in the acquisition and maintenance of self-administration of two widely used stimulants, cocaine and nicotine.MethodsMale and female rats self-administered cocaine (0.4 mg/kg/infusion) or nicotine (0.03 mg/kg/infusion) daily under a fixed-ratio 1 (FR 1) schedule until acquisition criteria were met (maximum of 30 sessions). The self-administration criterion for cocaine was ≥20 infusions in a 2-h session and ≥5 infusions in a 1-h session for nicotine. Sex differences were assessed by examining the percentage of rats that met acquisition criteria, the number of sessions to meet criteria, and the number of infusions earned during the maintenance phase.ResultsA significantly higher percentage of male rats acquired both cocaine and nicotine self-administration than females, and males met acquisition criteria in fewer sessions. However, after criteria were met, females self-administered more cocaine than males during the first 5 days of maintenance. There were no sex differences in nicotine infusions post-acquisition.ConclusionsDifferences in acquisition amongst sexes can reveal factors that are integral to initiation of drug use, an often overlooked phase of drug addiction.