PT  - JOURNAL ARTICLE
AU  - Rajarsi Mandal
AU  - Vijay Kumar Kutala
AU  - Mahmood Khan
AU  - Iyyapu K. Mohan
AU  - Saradhadevi Varadharaj
AU  - Arun Sridhar
AU  - Cynthia A. Carnes
AU  - Tamás Kálai
AU  - Kálmán Hideg
AU  - Periannan Kuppusamy
TI  - <em>N</em>-Hydroxy-pyrroline Modification of Verapamil Exhibits Antioxidant Protection of the Heart against Ischemia/Reperfusion-Induced Cardiac Dysfunction without Compromising Its Calcium Antagonistic Activity
AID  - 10.1124/jpet.107.127167
DP  - 2007 Oct 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 119--127
VI  - 323
IP  - 1
4099  - http://jpet.aspetjournals.org/content/323/1/119.short
4100  - http://jpet.aspetjournals.org/content/323/1/119.full
SO  - J Pharmacol Exp Ther2007 Oct 01; 323
AB  - Any clinical intervention (e.g., coronary angioplasty, thrombolysis) used to reintroduce blood flow to an ischemic region of the myocardium is accompanied by a complex enzymatic cascade of reactions resulting in severe injury to the heart, termed myocardial ischemia/reperfusion (I/R) injury. In this study, we evaluated the ability of H-3010 (1-hydroxy-2,2,5,5-tetramethyl-2,5-dihydro-1H-pyrrole-3-carboxylic acid (2-(3,4-dimethoxyphenyl)-5-([2-(3,4-dimethoxyphenyl)ethyl]-methylamino)-2-isopropylpentyl)-amide), a pyrroline modification of verapamil (2-(3,4-dimethoxyphenyl)-5-[2-(3,4-dimethoxyphenyl)ethylmethyl-amino]-2-(1-methylethyl)pentanenitrile), to protect the heart against I/R-mediated injury. Isolated perfused rat hearts pretreated with verapamil and H-3010 were subjected to 30 min of global no-flow ischemia followed by 45 min of reperfusion. The recovery (expressed as a percentage of preischemic baseline) in contractile function (left ventricular developed pressure) of hearts subjected to I/R was significantly higher in hearts treated with H-3010 at 5 μM (51.0 ± 6.4%) as well as at 50 μM (75.1 ± 7.4%) as compared with verapamil at 5 μM (32.2 ± 3.7%) or untreated control hearts (18.1 ± 2.8%). Creatine kinase release was significantly attenuated in hearts treated with H-3010 (45.7 ± 4.5 U/liter) as compared with untreated controls (131.5 ± 6.4 U/liter). Similar trends were also observed for lactate dehydrogenase release as well. A marked reduction in percent area of infarction was observed in the H-3010 group (11.7 ± 1.6%) compared with verapamil (25.1 ± 2.9%) and control (41.3 ± 1.9%) groups. Additional in vitro studies showed a marked decrease in reactive oxygen species generation with H-3010. In conclusion, our data clearly demonstrated that the verapamil derivative, H-3010, significantly decreased I/R-induced cardiac dysfunction. This can be attributed to the combined benefits of the pyrroline moiety (antioxidant) and the parent verapamil component (antiarrhythmic) in the protection of the heart from I/R-induced injury. The American Society for Pharmacology and Experimental Therapeutics