Studies on the mechanisms for vestibular adaptation of the bilateral labyrinthectomized infant rat

单侧睾丸切除动物表现出平衡功能障碍和眼球震颤。然而，这些发现通常在一段时间后消失。人们认为平衡功能障碍的改善是由大脑的可塑性引起的，称为前庭补偿。双侧睾丸切除动物仍有平衡功能障碍。因此，通常的前庭代偿在双侧前庭切除的动物中不易发挥作用。另一方面，先天性双侧膝关节缺陷的人表现出正常的平衡性发展。预测新生动物双侧延髓破坏时，平衡功能发育正常。双侧小脑切除后新生动物平衡功能障碍的改善与脑可塑性有关，本实验旨在探讨这一机制，特别是MAP激酶对脑神经元分化的影响。这些双侧睾丸切除的新生大鼠显示平衡功能的正常发育。迷路破坏后4天MAP激酶激活。然而，我们看到成年大鼠和新生大鼠之间的差异很小。因此，认为MAP激酶在脑的可塑性中不起重要作用。

Unilateral labyrinthectomized animal shows dysfunction of equilibrium and nystagmus. However these findings usually disapear after a while. It is thought that the improvement of dysfunction of equilibrium is caused by the plasticity of the brain which is called vestibular compensation. Bilateral labyrinthectomized animal remains the dysfunction of equilibrium. Therefore, usual vestibular compensation is not easy to work in bilateral labyrinthectomized animal. On the other hand, person with congenital deficit of bilateral labyrinths shows normal devalopment of equilibrium. It is forecast that the development of the equilibrium function is normal when bilateral labyrinths of newborn animalare destroyed. The improvement of dysfunction of equilibrium in bilateral labyrinthectomized newborn animal is due to the mechanism which is concerned with the plasticity of the brain.We aimed to examine this mechanism, Especially, we foces on the participation of MAP kinase which affects on the differentiation of the nuron of the brain.We destroyed bilateral labyrinths of newborn rats. These bilateral labyrinthectomized newborn rats showed normal development of the function of equilibrium. MAP kinase ia activated 4 days after the destruction of labyrinth. However, we saw little difference between in adult rats and in newborn rats. Therefore, it was thought that MAP kinase did not play an important role in the plasticity of the brain.