Decision-making is a complex process essential to daily adaptation in many species. Risk is an inherent aspect of decision-making and it is influenced by gonadal hormones. Testosterone and 17β-estradiol may modulate decision making and impact the mesocorticolimbic dopamine pathway. Here, we explored sex differences, the effect of gonadal hormones and the dopamine agonist amphetamine on risk-based decision making. Intact or gonadectomised (GDX) male and female rats underwent to a probabilistic discounting task. High and low doses of testosterone propionate (1.0 or 0.2 mg) and 17β-estradiol benzoate (0.3 μg) were administered to assess acute effects on risk-based decision making. After 3-days of washout period, intact and GDX rats received high or low (0.5 or 0.125 mg/kg) doses of amphetamine and re-tested in the probabilistic discounting task. Under baseline conditions, males made more risky choices during probability discounting compared to female rats, particularly in the lower probability blocks, but GDX did not influence risky choice. The high, but not the low dose, of testosterone modestly reduced risky decision making in GDX male rats. Conversely, 17β-estradiol had no significant effect on risky choice regardless of GDX status in either sex. Lastly, a higher dose of amphetamine increased risky decision making in both intact males and females, but had no effect in GDX rats. These findings demonstrated sex differences in risk-based decision making, with males showing a stronger bias toward larger, uncertain rewards. GDX status influenced the effects of amphetamine, suggesting different dopaminergic regulation in risk-based choices among males and females.

决策是许多物种日常适应所必需的复杂过程。风险是决策的固有方面，并且受性腺激素的影响。睾丸激素和17β-雌二醇可能会调节决策并影响中皮质糖皮质多巴胺途径。在这里，我们探讨了性别差异，性腺激素和多巴胺激动剂苯丙胺对基于风险的决策的影响。完整或经过性腺切除术（GDX）的雄性和雌性大鼠接受了概率性贴现任务。给予高剂量和低剂量的丙酸睾丸酮（1.0或0.2 mg）和17β-雌二醇苯甲酸酯（0.3μg），以评估对基于风险的决策的急性影响。清除期3天后，完整和GDX大鼠接受高剂量或低剂量（0.5或0.125 mg / kg）的苯丙胺，并在概率折扣任务中重新进行测试。在基线条件下，与雌性大鼠相比，在概率折现中，雄性做出的风险选择更多，特别是在概率较低的区域，但GDX不会影响风险选择。高剂量但不是低剂量的睾丸激素会适度降低GDX雄性大鼠的风险决策。相反，无论男女性别的GDX状况如何，17β-雌二醇对风险选择均无显着影响。最后，较高剂量的苯丙胺对完整的雄性和雌性动物都增加了危险的决策，但对GDX大鼠没有影响。这些发现表明，在基于风险的决策中，性别存在差异，男性对更大，不确定的报酬表现出更大的偏见。GDX的状态影响了苯丙胺的作用，表明男性和女性在基于风险的选择中有不同的多巴胺能调节。与雌性大鼠相比，雄性在概率折现过程中做出了更多的风险选择，尤其是在概率较低的区域，但GDX不会影响风险选择。高剂量但不是低剂量的睾丸激素会适度降低GDX雄性大鼠的风险决策。相反，无论男女性别的GDX状况如何，17β-雌二醇对风险选择均无显着影响。最后，较高剂量的苯丙胺对完整的雄性和雌性动物都增加了危险的决策，但对GDX大鼠没有影响。这些发现表明，在基于风险的决策中，性别存在差异，男性对更大，不确定的报酬表现出更大的偏见。GDX的状态影响了苯丙胺的作用，表明男性和女性在基于风险的选择中有不同的多巴胺能调节。与雌性大鼠相比，雄性在概率折现过程中做出了更多的风险选择，尤其是在概率较低的区域，但GDX不会影响风险选择。高剂量但不是低剂量的睾丸激素会适度降低GDX雄性大鼠的风险决策。相反，无论男女性别的GDX状况如何，17β-雌二醇对风险选择均无显着影响。最后，较高剂量的苯丙胺对完整的雄性和雌性动物都增加了危险的决策，但对GDX大鼠没有影响。这些发现表明，在基于风险的决策中，性别存在差异，男性对更大，不确定的报酬表现出更大的偏见。GDX的状态影响了苯丙胺的作用，表明男性和女性在基于风险的选择中有不同的多巴胺能调节。