The vasopressin-vasotocin (AVP-AVT) and oxytocin-mesotocin-isotocin (OT-MT-IT) families of nonapeptides are of great importance in shaping context-dependent modulations of a conserved and yet highly plastic network of brain areas involved in social behavior: the social behavior network. The nonapeptide systems of teleost fish are highly conserved and share a common general organization. In this study, we first describe the presence of IT cells and projections in the brain of an electric fish, Gymnotus omarorum. Second, we confirm that IT neuron types and distribution in the preoptic area (POA) follow the same general pattern previously described in other teleost species. Third, we show that although IT and AVT neurons occur intermingled within the POA of G. omarorum and can be classified into the same subgroups, they present subtle but remarkable differences in size, number, and location. Finally, we show that unlike AVT, IT has no effect on basal electric signaling, reinforcing the specificity in the actions that each one of these nonapeptides has on social behavior and communication.

九肽的加压素-血管收缩素 (AVP-AVT) 和催产素-中产素-异产素 (OT-MT-IT) 家族对于塑造与社会行为有关的保守且高度可塑性的大脑区域网络的上下文依赖性调制非常重要: 社会行为网络。硬骨鱼的九肽系统高度保守并具有共同的一般组织。在这项研究中，我们首先描述了电鱼Gymnotus omarorum 大脑中 IT 细胞和突起的存在。其次，我们确认视前区 (POA) 中的 IT 神经元类型和分布遵循先前在其他硬骨鱼物种中描述的相同一般模式。第三，我们表明尽管 IT 和 AVT 神经元混合出现在G. omarorum的 POA 中并且可以分为相同的亚组，它们在大小、数量和位置上存在细微但显着的差异。最后，我们表明，与 AVT 不同，IT 对基础电信号没有影响，从而增强了这些九肽中每一种对社会行为和交流的作用的特异性。