SYNTHESIS AND RELEASE OF BIOGENIC AMINES

这些研究主要集中在酪氨酸的调节特性上。 羟基酶、色氨酸羟基酶、一氧化氮合酶和 它们在生物合成和释放中的辅因子四氢生物蝶呤(BH4) 大脑中的儿茶酚胺和5-羟色胺。 我们已经证实，一氧化氮(NO)来源于L-精氨酸通过 一氧化氮合酶的作用增强了纹状体脑片中的多巴胺释放。这 这种作用可被一氧化氮合酶抑制剂--硝基精氨酸所抑制。我们有 也证实了BH4也促进了纹状体中多巴胺的释放 切片。我们的研究表明，L-精氨酸对大鼠心脏的兴奋作用。 增强多巴胺释放可以在脑片中减少 细胞内的BH4水平已经耗尽。BH4耗尽和 抑制一氧化氮合酶同样有效阻断L-精氨酸- 介导的多巴胺释放的刺激。这一发现支持 结论L-精氨酸介导的刺激多巴胺释放 依赖于BH4。 我们已经从大鼠和牛脑中提纯了14-3-3蛋白，并 探讨14-3-3在人重组蛋白表达调控中的作用 色氨酸羟化酶(与麦芽糖结合蛋白融合)在 大肠埃希菌。融合色氨酸羟基酶在 CAMP依赖蛋白激酶和钙调蛋白依赖蛋白的表达 初步结果表明，凝胶漂移试验使用天然的 聚丙烯酰胺凝胶显示没有形成复合体。亲和力 融合酶共价偶联的层析实验 与Affi Gel-10的活性酯表明14-3-3没有结合 用偶联的酶。

These studies have focused on the regulatory properties of tyrosine hydroxylase, tryptophan hydroxylase, nitric oxide synthase (NOS) and their cofactor tetrahydrobiopterin (BH4) in the biosynthesis and release of catecholamine and serotonin in the brain. We have confirmed that nitric oxide (NO) derived from L-arginine through the action of NOS enhances dopamine release in striatal slices. This effect can be inhibited by the NOS inhibitor-nitro arginine. We have also confirmed that BH4 also enhances dopamine release in striatal slices. Our studies show that the stimulating effect of L-arginine in enhancing dopamine release can be decreased in the slices in which the intracellular BH4 levels have been depleted. BH4 depletion and inhibition of NOS are equally effective in blocking the L-arginine- mediated stimulation of dopamine release. This finding supports the conclusion that the L-arginine-mediated stimulation of dopamine release is BH4 dependent. We have purified the 14-3-3 protein from rat and bovine brains and investigated the role of 14-3-3 in the regulation of human recombinant tryptophan hydroxylase (fused with maltose binding protein) expressed in E.coli. Fusion tryptophan hydroxylase was phosphorylated in the presence of both cAMP-dependent protein kinase and calmodulin-dependent protein kinase II. Preliminary results showed that gel shift assay using native polyacrylamide gel indicated no complex formation. Affinity chromatography experiments where fusion enzyme was covalently coupled with the activated ester of Affi gel-10 indicated no binding of 14-3-3 with the coupled enzyme.