Department of Chemistry, Faculty of Science, Atatürk University, Erzurum, Turkey.
Department of Primary Education, Faculty of Education, Bayburt University, Bayburt, Turkey.
Pharmacol Rep. 2014 Feb;66(1):74-80. doi: 10.1016/j.pharep.2013.08.007. Epub 2014 Feb 3.
In this study, we investigated the in vitro effects of calcium channel blockers (nifedipine, nitrendipine, isradipine, and amlodipine besylate) on the activity of paraoxonase-1 (PON1).
PON1 was purified from human serum using simple chromatographic methods, including DEAE-Sephadex anion-exchange and Sephadex G-200 gel filtration chromatography.
The calcium channel blockers decreased the in vitro PON1 activity. The inhibition mechanism of amlodipine besylate was noncompetitive, whereas nifedipine, nitrendipine, and isradipine were competitive inhibitors.
Our results showed that calcium channel blockers exhibit inhibitory effects on PON1 at low concentrations. The IC(50) values for nifedipine, nitrendipine, isradipine, and amlodipine besylate were determined to be 0.121 mM, 0.130 mM, 0.255 mM, and 0.304 mM, respectively, and the K(i) constants were calculated to be 0.222 ± 0.049 mM, 0.151 ± 0.067 mM, 0.286 ± 0.137 mM, and 0.321 ± 0.002 mM, respectively.
本研究旨在探讨钙通道阻滞剂（硝苯地平、尼群地平、异乐定和苯磺酸氨氯地平）对人血清对氧磷酶-1（PON1）活性的体外影响。
采用简单的色谱方法，包括 DEAE-葡聚糖阴离子交换和葡聚糖凝胶 G-200 过滤层析法，从人血清中纯化 PON1。
钙通道阻滞剂降低了体外 PON1 活性。苯磺酸氨氯地平的抑制机制是非竞争性的，而硝苯地平、尼群地平、异乐定则为竞争性抑制剂。
本研究结果表明，钙通道阻滞剂在低浓度下对 PON1 表现出抑制作用。硝苯地平、尼群地平、异乐定和苯磺酸氨氯地平的 IC50 值分别为 0.121、0.130、0.255 和 0.304 mM，K i 值分别为 0.222±0.049、0.151±0.067、0.286±0.137 和 0.321±0.002 mM。
