The effects of sex, estrous cycle, and social contact on cocaine and heroin self-administration in rats.
The effects of sex, estrous cycle, and social contact on cocaine and heroin self-administration in rats.
复制标题
性别，发情周期和社会接触对大鼠可卡因和海洛因自我管理的影响。
DOI：
10.1007/s00213-016-4368-9
复制
发表时间：
2016-09
影响因子：
3.4
通讯作者：
Smith MA
中科院分区：
文献类型：
--
作者：
Lacy RT;Strickland JC;Feinstein MA;Robinson AM;Smith MA
临床前研究表明，性腺激素是药物自我给药的重要决定因素。迄今为止，在生态相关的社会背景下，对性和发情周期对药物自我给药的影响知之甚少。在雄性-雌性和雌性-雌性社会二联体的大鼠模型中，检查性别和发情周期在可卡因和海洛因自我给药期间的作用。研究人员在操作性条件反射室中训练雄性和雌性未交配的大鼠自行服用可卡因和海洛因，这种条件反射室允许两只大鼠同时服用可卡因和海洛因，但禁止身体接触。实验1考察了男性-女性双体可卡因自我给药的递进比例。实验2和实验3分别考察了在固定比例计划下，在恒定剂量和不同剂量下，男性和女性对海洛因的自我给药。实验四考察了固定比例的雌雄双体海洛因自我给药情况。在发情期间，可卡因维持的断点在女性中增加了约17%，但在男性中保持不变。无论隔离、与雄鼠同住或与雌鼠同住，雌鼠在发情期海洛因自我给药减少约70%。在某些情况下，男性的海洛因自我给药率低于女性，并且与女性的反应不一致。当有男性伴侣在场时，女性的发情周期会影响可卡因和海洛因的自我服用。作为一项新的发现，这些数据表明，无论社会背景如何，女性在发情期的海洛因自我使用都会减少。最后，这些数据表明，男性自我给药仅受女性伴侣荷尔蒙状况的影响很小。
Preclinical studies indicate that gonadal hormones are important determinants of drug self-administration. To date, little is known about the influence of sex and estrous cycle on drug self-administration in ecologically relevant social contexts. Examine the role of sex and estrous cycle in a rat model during cocaine and heroin self-administration with male-female and female-female social dyads. Male and female virgin rats were trained to self-administer cocaine and heroin in operant conditioning chambers that permitted two rats to self-administer concurrently but prevented physical contact. Experiment 1 examined cocaine self-administration on a progressive-ratio schedule in male-female dyads. Experiments 2 and 3 examined heroin self-administration on a fixed-ratio schedule in male-female dyads at constant and varying doses, respectively. Experiment 4 examined heroin self-administration in female-female dyads on a fixed-ratio schedule. Cocaine-maintained breakpoints increased by ~17% in females during estrus but remained consistent in males. Heroin self-administration decreased by ~70% during proestrus in females whether they were isolated, housed with males, or housed with females. Heroin self-administration was lower in males than females under some conditions and was not consistently associated with the responding of females. Cocaine and heroin self-administration is influenced by the estrous cycle in females when in the presence of a male partner. As a novel finding, these data illustrate that heroin self-administration is reduced in females during proestrus regardless of the social context tested. Finally, these data suggest that drug self-administration in males is only minimally influenced by the hormonal status of a female partner.