Dopamine is present in all vertebrates and the functional roles of the subsystems are assumed to be similar. Whereas the effect of dopaminergic modulation is well investigated in different target systems, less is known about the factors that are causing the modulation of dopaminergic cells. Using the zebra mbuna, Pseudotropheus zebra, a cichlid fish from Lake Malawi as a model system, we investigated the activation of specific dopaminergic cell populations detected by double-labeling with TH and pS6 antibodies while the animals were solving different learning tasks. Specifically, we compared an intense avoidance learning situation, an instrumental learning task, and a non-learning isolated group and found strong activation of different dopaminergic cell populations. Preoptic-hypothalamic cell populations respond to the stress component in the avoidance task, and the forced movement/locomotion may be responsible for activation in the posterior tubercle. The instrumental learning task had little stress component, but the activation of the raphe superior in this group may be correlated with attention or arousal during the training sessions. At the same time, the weaker activation of the nucleus of the posterior commissure may be related to positive reward acting onto tectal circuits. Finally, we examined the co-activation patterns across all dopaminergic cell populations and recovered robust differences across experimental groups, largely driven by hypothalamic, posterior tubercle, and brain stem regions possibly encoding the valence and salience associated with stressful stimuli. Taken together, our results offer some insights into the different functions of the dopaminergic cell populations in the brain of a non-mammalian vertebrate in correlation with different behavioral conditions, extending our knowledge for a more comprehensive view of the mechanisms of dopaminergic modulation in vertebrates.

多巴胺存在于所有脊椎动物中，并且子系统的功能作用被认为是相似的。尽管多巴胺能调节的作用在不同的靶系统中得到了很好的研究，但对于引起多巴胺能细胞调节的因素却知之甚少。我们使用斑马 mbuna（Pseudotropeus zebra）（一种来自马拉维湖的慈鲷）作为模型系统，研究了在动物解决不同学习任务时通过 TH 和 pS6 抗体双标记检测到的特定多巴胺能细胞群的激活情况。具体来说，我们比较了强烈的回避学习情况、工具性学习任务和非学习隔离组，发现不同的多巴胺能细胞群有强烈的激活作用。视前下丘脑细胞群对回避任务中的应激成分做出反应，并且强迫运动/运动可能是后结节激活的原因。器乐学习任务几乎没有压力成分，但该组中缝上的激活可能与训练期间的注意力或唤醒相关。同时，后连合核的激活较弱可能与作用于顶盖回路的正奖励有关。最后，我们检查了所有多巴胺能细胞群的共激活模式，并恢复了实验组之间的显着差异，这主要是由下丘脑、后结节和脑干区域驱动的，这些区域可能编码与压力刺激相关的效价和显着性。总而言之，我们的结果为非哺乳动物脊椎动物大脑中多巴胺能细胞群与不同行为条件相关的不同功能提供了一些见解，扩展了我们的知识，以便更全面地了解脊椎动物多巴胺能调节机制。