Saponara Simona, Kawase Masami, Shah Anamik, Motohashi Noboru, Molnar Joseph, Ugocsai Katalin, Sgaragli Giampietro, Fusi Fabio
Istituto di Scienze Farmacologiche, Università degli Studi di Siena, via A. Moro 2, 53100 Siena, Italy.
Br J Pharmacol. 2004 Feb;141(3):415-22. doi: 10.1038/sj.bjp.0705635. Epub 2004 Jan 12.
The aim of this study was to investigate the effects of 3,5-diacetyl- (DP1-DP5) and 3,5-dibenzoyl-1,4-dihydropyridines (DP6-DP11) on vascular functions in vitro, by comparing their mechanical and electrophysiological actions in rat aorta rings and single rat tail artery myocytes, respectively, and to quantify their multidrug resistance (MDR)-reversing activity in L5178 Y mouse T-lymphoma cells transfected with MDR1 gene. In rat aorta, the 11 compounds tested, but 3,5-dibenzoyl-4-(3-phenoxyphenyl)-1,4-dihydro-2,6-dimethylpyridine (DP7), 3,5-dibenzoyl-4-(3-chlorophenyl)-1,4-dihydro-2,6-dimethylpyridine (DP9), 3,5-dibenzoyl-4-(4-chlorophenyl)-1,4-dihydro-2,6-dimethylpyridine (DP10) and 3,5-dibenzoyl-4-phenyl-1,4-dihydro-2,6-dimethylpyridine (DP11), antagonized 60 mm K+ (K60)-induced contraction in a concentration-dependent manner, with IC50 (m) values ranging between 5.65 x 10(-7) and 2.23 x 10(-5). The 11 dihydropyridines tested, but DP7, inhibited L-type Ca2+ current recorded in artery myocytes in a concentration-dependent manner, with IC50 (M) values ranging between 1.12 x 10(-6) and 6.90 x 10(-5). The K+ -channel opener cromakalim inhibited the Ca2+ -induced contraction in K30 but not that evoked in K60. On the contrary, DP7 was ineffective in both experimental conditions. When the rings were preincubated with 1 mm Ni2+ plus 1 microm nifedipine, the response to phenylephrine was significantly reduced by 2,5-di-t-butyl-1,4-benzohydroquinone (BHQ), a well-known endoplasmic reticulum Ca2+ -ATPase inhibitor. DP7 had no effects on this model system. In L5178 MDR cell line, the 11 dihydropyridines tested, but 3,5-diacetyl-4-(2-nitrophenyl)-1,4-dihydro-2,6-dimethylpyridine (DP1), 3,5-diacetyl-4-(3-phenoxyphenyl)-1,4-dihydro-2,6-dimethylpyridine (DP2) and 3,5-diacetyl-4-(3-chlorophenyl)-1,4-dihydro-2,6-dimethylpyridine (DP4), exhibited an MDR-reversing activity, with IC50 values ranging between 3.02 x 10(-7) and 4.27 x 10(-5), DP7 being the most potent. In conclusion, DP7 may represent a lead compound for the development of potent dihydropyridine MDR chemosensitizers devoid of vascular effects. British Journal of Pharmacology (2004) 141, 415-422. doi:10.1038/sj.bjp.0705635
本研究旨在通过分别比较3,5 - 二乙酰基 - 1,4 - 二氢吡啶（DP1 - DP5）和3,5 - 二苯甲酰基 - 1,4 - 二氢吡啶（DP6 - DP11）在大鼠主动脉环和大鼠单尾动脉肌细胞中的力学和电生理作用，来研究它们对体外血管功能的影响，并量化它们在转染了MDR1基因的L5178Y小鼠T淋巴瘤细胞中的多药耐药（MDR）逆转活性。在大鼠主动脉中，所测试的11种化合物中，除3,5 - 二苯甲酰基 - 4 -（3 - 苯氧基苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP7）、3,5 - 二苯甲酰基 - 4 -（3 - 氯苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP9）、3,5 - 二苯甲酰基 - 4 -（4 - 氯苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP10）和3,5 - 二苯甲酰基 - 4 - 苯基 - 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP11）外，均以浓度依赖性方式拮抗60 mM K⁺（K60）诱导的收缩，IC50（m）值在5.65×10⁻⁷至2.23×10⁻⁵之间。所测试的11种二氢吡啶中，除DP7外，均以浓度依赖性方式抑制动脉肌细胞中记录的L型Ca²⁺电流，IC50（M）值在1.12×10⁻⁶至6.90×10⁻⁵之间。钾通道开放剂克罗卡林抑制K30中Ca²⁺诱导的收缩，但不抑制K60中诱发的收缩。相反，DP7在两种实验条件下均无效。当主动脉环用1 mM Ni²⁺加1 μM硝苯地平预孵育时，2,5 - 二叔丁基 - 1,4 - 苯二酚（BHQ）（一种著名的内质网Ca²⁺ - ATP酶抑制剂）可显著降低对去氧肾上腺素的反应。DP7对该模型系统无影响。在L5178 MDR细胞系中，所测试的11种二氢吡啶中，除3,5 - 二乙酰基 - 4 -（2 - 硝基苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP1）、3,5 - 二乙酰基 - 4 -（3 - 苯氧基苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP2）和3,5 - 二乙酰基 - 4 -（3 - 氯苯基）- 1,4 - 二氢 - 2,6 - 二甲基吡啶（DP4）外，均表现出MDR逆转活性，IC50值在3.02×10⁻⁷至4.27×10⁻⁵之间，DP7最为有效。总之，DP7可能代表一种开发强效无血管效应的二氢吡啶MDR化学增敏剂的先导化合物。《英国药理学期刊》（2004年）141卷，415 - 422页。doi:10.1038/sj.bjp.0705635
