Tarmati Valeria, Sepe Andrea, Accoto Alessandra, Conversi David, Laricchiuta Daniela, Panuccio Anna, Canterini Sonia, Fiorenza Maria Teresa, Cabib Simona, Orsini Cristina
Department of Psychology, Sapienza University of Rome, Rome, Italy.
PhD Program in Behavioral Neuroscience, Department of Psychology, Sapienza University of Rome, Rome, Italy.
Psychopharmacology (Berl). 2025 Jun;242(6):1275-1289. doi: 10.1007/s00213-024-06726-2. Epub 2024 Dec 12.
The specific location of deviations from normative models of brain function varies considerably across individuals with the same diagnoses. However, as pathological processes are distributed across interconnected systems, this heterogeneity of individual brain deviations may also reveal similarities and differences between disorders. The paraventricular nucleus of the thalamus (PVT) is a potential switcher to various behavioral responses where functionally distinct cell types exist across its antero-posterior axis.
This study aimed to test the hypothesis that genotype-dependent differences in the anterior and posterior PVT subregions (aPVT and pPVT) are involved in the Sign-tracking (ST) behavior expressed by C57BL/6J (C57) and DBA/2J (DBA) inbred mice.
Based on previous findings, male mice of the two strains were tested at ten weeks of age. The density of c-Fos immunoreactivity along the antero-posterior axis of PVT was assessed following the expression of ST behavior. Selective excitotoxic lesions of the aPVT or the pPVT by the NMDA infusion were performed prior to development of ST behavior. Finally, the distribution of neuronal populations expressing the Drd2 and Gal genes (D2R + and Gal +) was measured by in situ hybridization (ISH).
The involvement of PVT subregions in ST behavior is strain-specific, as aPVT is crucial for ST acquisition in DBA mice while pPVT is crucial for C57 mice. Despite similar antero-posterior distribution of D2R + and Gal + neurons, density of D2R + neurons differentiate aPVT in C57 and DBA mice.
These genotype-dependent results offer valuable insights into the nuanced organization of brain networks and individual variability in behavioral responses.
在患有相同诊断的个体中，与大脑功能规范模型的偏差的具体位置存在很大差异。然而，由于病理过程分布在相互连接的系统中，个体大脑偏差的这种异质性也可能揭示不同疾病之间的异同。丘脑室旁核（PVT）是各种行为反应的潜在切换器，其前后轴上存在功能不同的细胞类型。
本研究旨在检验以下假设：PVT前区和后区（aPVT和pPVT）的基因型依赖性差异与C57BL/6J（C57）和DBA/2J（DBA）近交系小鼠表现出的信号追踪（ST）行为有关。
根据先前的研究结果，对这两个品系的雄性小鼠在10周龄时进行测试。在ST行为表达后，评估PVT前后轴上c-Fos免疫反应性的密度。在ST行为发展之前，通过注入NMDA对aPVT或pPVT进行选择性兴奋性毒性损伤。最后，通过原位杂交（ISH）测量表达Drd2和Gal基因（D2R+和Gal+）的神经元群体的分布。
PVT亚区参与ST行为具有品系特异性，因为aPVT对DBA小鼠的ST获得至关重要，而pPVT对C57小鼠至关重要。尽管D2R+和Gal+神经元在前后分布上相似，但D2R+神经元的密度在C57和DBA小鼠的aPVT中有所不同。
这些基因型依赖性结果为大脑网络的细微组织和行为反应中的个体变异性提供了有价值的见解。
