Further Insights into the Influence of <scp>l</scp>-Cysteine on the Oxidation Chemistry of Dopamine: Reaction Pathways of Potential Relevance to Parkinson's Disease
作者:Xue-Ming Shen、Glenn Dryhurst
DOI:10.1021/tx960008f
日期:1996.1.1
normally found in the cytoplasm of dopaminergic cell bodies in the substantia nigra (SN), is the autoxidation of dopamine (DA) to DA-o-quinone (1). In this investigation, it is demonstrated that in the presence of L-cysteine (CySH) o-quinone 1 is scavenged to give 5-S-cysteinyldopamine (5-S-Cys-DA, major product) and 2-S-cysteinyldopamine (2-S-CyS-DA, minor product). These cysteinyl conjugates are more easily
神经黑色素(一种通常在黑质(SN)的多巴胺能细胞体细胞质中发现的黑色聚合色素)的形成的第一步是将多巴胺(DA)自动氧化为DA-o-醌(1)。在这项研究中,证明了在存在L-半胱氨酸(CySH)的情况下,邻醌1会被清除,生成5-S-半胱氨酰多巴胺(5-S-Cys-DA,主要产品)和2-S-半胱氨酰多巴胺( 2-S-CyS-DA,次要产品)。这些半胱氨酰缀合物比DA更容易被氧化。所得产物的相对产率取决于游离CySH的浓度。这些产品包括2,5-双-S-半胱氨酸多巴胺(2,5-bi-S-CyS-DA)和2,5,6-三-S-半胱氨酰多巴胺(2,5,6-三-S-CyS-DA DA),7-(2-氨基乙基)-3,4-二氢-5-羟基-2H-1,4-苯并噻嗪-3-羧酸(DHBT-1),8-(2-氨基乙基)-3,4 -二氢-5-羟基-2H-1 4-苯并噻嗪-3-羧酸(DHBT-5),以及这些二氢苯并噻嗪(DHBT)的许多半胱氨酸共轭物。当将2