Cook Anna-Louise M, Haynes John M
School of Biomedical Sciences, Curtin University of Technology, Bentley, WA, USA.
Nitric Oxide. 2007 Feb;16(1):10-7. doi: 10.1016/j.niox.2006.09.003. Epub 2006 Sep 14.
Nitric oxide (NO) is known to regulate contractility and proliferation of cells within the prostate, however, the mechanism by which this occurs is unknown. The cGMP-dependent protein kinase (PKG) signalling pathway may be involved, and recent work has shown that activation of this pathway can be assessed by analysis of phosphorylation of vasodilator-stimulated phosphoprotein (VASP). The aim of the current study is to characterise the expression of VASP in the human prostate and human cultured prostatic stromal cells (HCPSCs), and to investigate whether NO activates PKG in these cells. Our studies revealed that VASP is expressed, and that incubation of HCPSCs with PKG-activating cGMP-analogues or the NO-donor, SNP, caused a significant PKG-dependent increase in VASP serine-239 phosphorylation. In addition, SNP elicited a reduction in intracellular K(+) in a time frame consistent with the phosphorylation of VASP and activation of PKG. These data demonstrate that VASP can be used to assess the NO/cGMP/PKG signalling pathway in HCPSCs. In addition, we demonstrate for the first time that SNP, probably via NO release, leads to phosphorylation of VASP in a manner consistent with PKG activation.
已知一氧化氮（NO）可调节前列腺内细胞的收缩性和增殖，然而，其发生机制尚不清楚。环磷酸鸟苷（cGMP）依赖性蛋白激酶（PKG）信号通路可能参与其中，最近的研究表明，该通路的激活可通过分析血管舒张刺激磷蛋白（VASP）的磷酸化来评估。本研究的目的是表征VASP在人前列腺和人培养的前列腺基质细胞（HCPSC）中的表达，并研究NO是否能激活这些细胞中的PKG。我们的研究表明VASP有表达，并且用PKG激活剂cGMP类似物或NO供体硝普钠（SNP）孵育HCPSC会导致VASP丝氨酸239磷酸化显著增加，且依赖于PKG。此外，SNP在与VASP磷酸化和PKG激活一致的时间范围内引起细胞内钾离子（K⁺）减少。这些数据表明VASP可用于评估HCPSC中的NO/cGMP/PKG信号通路。此外，我们首次证明SNP可能通过释放NO，以与PKG激活一致的方式导致VASP磷酸化。
