Castration, dopamine and food choice: a cost/benefit test in male hamsters.
Castration, dopamine and food choice: a cost/benefit test in male hamsters.
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阉割、多巴胺和食物选择：雄性仓鼠的成本/效益测试。
DOI：
10.1016/s0166-4328(02)00101-8
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发表时间：
2002
影响因子：
2.7
通讯作者：
Wood,RuthI
中科院分区：
文献类型：
--
作者：
Chu,Lucy;Wood,RuthI
睾酮对于交配至关重要，并有助于性动机。此外，阉割的雄性更胖，也更不活跃，这表明雄激素可能在非性行为中发挥作用，包括与食物相关的反应。为了检验这一假设，雄性仓鼠接受了成本/效益测试的训练，该测试比较了对更喜欢的食物的操作反应与随意食用实验室食物的反应。男性在阉割之前和之后进行了测试。还确定了多巴胺拮抗剂氟哌啶醇对完整和阉割男性的仪器反应的影响。在每日 30 分钟的测试（665 次按压，6.0±0.9 g）中，食物匮乏的仓鼠对 45 mg Bio-Serv 颗粒反应强烈。当实验室食物可用时，雄性继续对颗粒饲料（3.6±0.6 g）做出反应，而不是随意进食（1.2±0.3 g）。多巴胺是这种反应的核心，因为氟哌啶醇 (1.0 mg/kg i.p.) 逆转了食物摄入量（颗粒：0.5±0.1 g；饲料 2.0±0.5 g）。去势对单独丸粒（6.6±0.7 g）的操作反应没有影响。当有食物时，去势者以颗粒形式消耗的食物占其总食物摄入量的比例甚至更高[6.0±0.4克颗粒食品（92％），1.6±0.5克饲料（8％），而完整雄性分别为75％和25％]。这与我们最初的假设相反。此外，去势并没有改变氟哌啶醇对食物摄入的影响：（0.4±0.1克颗粒；1.6±0.5克饲料）。这些结果支持了先前在大鼠中的发现，即多巴胺影响成本/效益测试中的反应分配。然而，他们不支持睾酮改变食物相关反应分配的假设。
Testosterone is essential for copulation, and contributes to sexual motivation. In addition, castrated males are fatter and less active, suggesting that androgens may play a role in non-sexual behaviors, including food-related responses. To test this hypothesis, male hamsters were trained with a cost/benefit test, which compares operant responding for more-preferred food versus ad libitum consumption of lab chow. Males were tested before and after castration. The effect of the dopamine antagonist, haloperidol, on instrumental responses in intact and castrated males was also determined. Food-deprived hamsters responded vigorously for 45 mg Bio-Serv pellets in daily 30-min tests (665 presses, 6.0±0.9 g). When lab chow was available, males continued to respond for pellets (3.6±0.6 g) over chow ad libitum (1.2±0.3 g). Dopamine is central to this response because haloperidol (1.0 mg/kg i.p.) reversed food intake (pellets: 0.5±0.1 g; chow 2.0±0.5 g). Castration had no effect on operant responding for pellets alone (6.6±0.7 g). When chow was present, castrates consumed an even greater proportion of their total food intake as pellets [6.0±0.4 g pellets (92%), 1.6±0.5 g chow (8%), vs. 75 and 25%, respectively, for intact males]. This is contrary to our original hypothesis. In addition, castration did not change the effects of haloperidol on food intake: (0.4±0.1 g pellets; 1.6±0.5 g chow). These results support previous findings in rats that dopamine affects response allocation in a cost/benefit test. However, they do not support the hypothesis that testosterone modifies the allocation of food-related responses.