Kiryu S, Morita N, Ohno K, Maeno H, Kiyama H
Department of Neuroanatomy, Osaka University Medical School, Japan.
Brain Res Mol Brain Res. 1995 Mar;29(1):147-56. doi: 10.1016/0169-328x(94)00241-6.
Using in situ hybridization histochemistry and immunohistochemistry, the present study examines the cooperative regulation of transcription of molecules involved in the Ras-signal and the cAMP dependent protein kinase (PKA) pathways during peripheral nerve regeneration in rats. Injury to hypoglossal motor neurons resulted in an increase in extracellular regulated kinase (ERK, or MAP kinase) and ERK kinase (MEK, or MAP kinase kinase) mRNAs, but in a decrease in the expression of the catalytic subunits of PKA (C alpha and C beta) mRNAs. These results show the importance of the Ras-signal pathway in the nerve regeneration process and extend recent observation which suggested a cross-talk between the Ras and PKA pathways in vitro. The down-regulation of PKA may facilitate the activation of the Ras pathway which is located downstream of the growth factor receptor. The present study may suggest a possibility of regulatory talk between these two major signal transduction pathways.
本研究运用原位杂交组织化学和免疫组织化学方法，检测大鼠外周神经再生过程中，Ras信号通路及环磷酸腺苷（cAMP）依赖性蛋白激酶（PKA）通路相关分子转录的协同调控。舌下运动神经元损伤导致细胞外调节激酶（ERK，即丝裂原活化蛋白激酶）和ERK激酶（MEK，即丝裂原活化蛋白激酶激酶）的信使核糖核酸（mRNA）增加，但PKA催化亚基（Cα和Cβ）的mRNA表达减少。这些结果表明Ras信号通路在神经再生过程中的重要性，并拓展了近期关于Ras与PKA通路在体外存在交互作用的观察结果。PKA的下调可能促进生长因子受体下游Ras通路的激活。本研究提示这两条主要信号转导通路之间可能存在调控交互作用。
