Differences in the effects of Na+-H+ exchange inhibitors on cardiac function and apoptosis in guinea-pig ischemia-reperfused hearts
Autor: | Tomohiro Takeo, Yoshihiro Hotta, Michio Yajima, Norio Kawai, Naohisa Ishikawa, Kazuto Yamada, Lei Huang, Naohito Ohashi, Hidetsugu Otsuka-Murakami, Haruaki Nishimaki, Kazuki Matsui, Gen Itoh, Setsuko Yamamoto |
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Rok vydání: | 2004 |
Předmět: |
Cardiac function curve
Male Programmed cell death Magnetic Resonance Spectroscopy Sodium-Hydrogen Exchangers Guinea Pigs Ischemia Apoptosis Blood Pressure Myocardial Reperfusion Injury Cell Separation Pharmacology In Vitro Techniques Mitochondria Heart Sodium-Calcium Exchanger Rats Sprague-Dawley Coronary circulation Nuclear magnetic resonance Cytosol Superoxides Coronary Circulation medicine In Situ Nick-End Labeling Animals Fluorometry Myocytes Cardiac Cation Transport Proteins Sodium-Hydrogen Exchanger 1 Sodium-calcium exchanger Chemistry Caspase 3 Hydroxyl Radical Myocardium Electron Spin Resonance Spectroscopy Membrane Proteins Heart Hydrogen-Ion Concentration medicine.disease Myocardial Contraction Rats Enzyme Activation Sodium–hydrogen antiporter medicine.anatomical_structure Caspases Female Reperfusion injury |
Zdroj: | European journal of pharmacology. 503(1-3) |
ISSN: | 0014-2999 |
Popis: | The protective effects of the Na+-H+ exchange (NHE) inhibitors SM-198110 (2-[[(aminoiminomethyl) amino] carbonyl]-4-chloro-1H-indole-1-propanesulfonic acid monohydrate) and SM-197378 (N-(aminoiminomethyl)-1-methyl-7-(sulfooxy)-4-(trifluoromethyl)-1H-indole-2-carboxamide monohydrate) were investigated in perfused Langendorff guinea-pig hearts subjected to ischemia (40 min) and reperfusion (40 min). The recovery of left ventricular developed pressure (LVDP) from ischemia by reperfusion was 39.0% in the control, while in the hearts pretreated with SM-198110 or SM-197378 (10(-7) M), it was about 100%. The ATP level, monitored simultaneously by (31)P-nuclear magnetic resonance spectrometry, was already higher than the control value at the end of the ischemic period, and the elevation in Na+ or Ca2+ fluorometric signals induced during ischemia was suppressed. In post-treated hearts, the LVDP recovery rate was significantly higher with SM-198110 than with SM-197378. By in vitro electron paramagnetic resonance spectrometry, SM-197378 was found to directly quench the active oxygen radical, whereas SM-198110 had no effect. Numbers of apoptotic cardiomyocytes after ischemia (1 h) followed by reperfusion (5 h) were significantly lower in SM-197378-treated than in SM-198110-treated hearts, consistent with the level of activity of caspase-3. These results suggest that the antioxidant effects of NHE inhibitors have an important role in apoptosis during ischemia-reperfusion, but apoptosis is not a major manifestation of cardiac function during postischemic recovery, and that NHE-sensitive mechanisms of reperfusion injury promote both necrotic and apoptotic processes death. |
Databáze: | OpenAIRE |
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