TESTOSTERONE AND CORTICAL DEVELOPMENT

阅读困难症是一种阅读学习障碍，通常表现为 先天的基础，男性比女性更常见。它 已经表明，长期或过度的发育激增 睾丸激素可能会扰乱大脑皮层的发育，并导致 读写困难症。在本提案中，通过使用以下方法来检验这一假设 将大鼠作为模型，使发育激素水平可以 被操纵了。过量的睾丸素将在出生后注射 发育(2-8天)皮质神经元迁移和 差异化。将有三个皮质区域(额叶、顶叶、视觉) 在断奶年龄对注射过量的雄性进行采样 睾丸素和注油对照组。我们将检查大脑皮层 通过尼氏染色观察皮质层的大小和胞体的大小 密度将被测量。树状树的大小作为 突触连接的指示器也将用高尔基体染色进行量化 横断面。据推测，暴露在过量的睾丸素中 会扰乱大脑皮层的组织。这可以作为一种 睾丸激素扰动可能以更微妙的形式影响的模型 在人类诵读困难症患者大脑皮质发育过程中。

Dyslexia is a disorder in learning to read that often appears to have a congenital basis and is found more frequently in males than in females. It has been suggested that a prolonged or excessive surge of developmental testosterone may disrupt the development of the cerebral cortex and result in dyslexia. In the present proposal, this hypothesis is tested by using the rat as a model so that developmental hormone levels can be manipulated. Excess testosterone will be injected during postnatal development (days 2-8) when cortical neurons are migrating and differentiating. Three cortical areas (frontal, parietal, visual) will be sampled in weaning age males that have been injected with excess testosterone and in oil injected controls. The cortices will be examined through Nissl stains where the size of the cortical layers and soma size and density will be measured. The size of the dendritic tree as an indicator of synaptic connectivity will also be quantified in Golgi stained sections. It is hypothesized that exposure to an excess of testosterone will disrupt the organization of the cerebral cortex. This can serve as a model for what testosterone perturbations could effect in more subtle form during the development of the cortex in human dyslexics.