Hirayama K, Kapatos G
Department of Psychiatry and Behavioral Neurosciences, Wayne State University School of Medicine, Detroit, MI 48201, USA.
Neurochem Int. 1995 Aug;27(2):157-61. doi: 10.1016/0197-0186(95)00008-v.
Monolayer cultures of superior cervical ganglia free of support cells were maintained in the presence of 100 ng/ml 7S-NGF for 4 days. The concentration of NGF was then changed to between 50 and 400 ng/ml and cultures continued for an additional 7 days. Tetrahydrobiopterin (BH4) content, GTP cyclohydrolase (GTPCH) enzyme activity and mRNA levels were then determined. All three of these measures were found to be elevated between 2- to 4-fold by treatment with increasing concentrations of NGF. Tyrosine hydroxylase (TH) enzyme activity and mRNA levels were increased from 8 to 13-fold by these same treatments. These results indicate that the content of BH4 within sympathetic neurons can be regulated by NGF receptor-mediated changes in GTPCH gene expression. Moreover, concomitant increases in TH enzyme activity and BH4 content demonstrate a coordinated regulation by NGF of this enzyme and its essential cofactor.
将不含支持细胞的颈上神经节单层培养物在100 ng/ml 7S-NGF存在的条件下培养4天。然后将NGF浓度改为50至400 ng/ml，并继续培养7天。随后测定四氢生物蝶呤（BH4）含量、GTP环化水解酶（GTPCH）酶活性和mRNA水平。发现随着NGF浓度增加进行处理后，所有这三项指标均升高了2至4倍。酪氨酸羟化酶（TH）酶活性和mRNA水平通过相同处理从8倍增加到13倍。这些结果表明，交感神经元内BH4的含量可通过NGF受体介导的GTPCH基因表达变化来调节。此外，TH酶活性和BH4含量的同时增加表明NGF对该酶及其必需辅因子具有协同调节作用。
