Abstract 11859: Percutaneous Carbon Dioxide Gas Mist Treatment Improves Cardiac Function after Myocardial Infarction in Rats via Nitric Oxide Activity
Background: We have recently reported that carbon dioxide (CO2) mist, which dissolved CO2 gas in H2O could improve cardiac function after myocardial infarction (MI) and increase the concentration of CO2 levels in the myocardium. However, its precise mechanisms remain unclear.
Hypothesis: We hypothesized that percutaneously administered CO2 mist would improve cardiac function via nitric oxide (NO) activity.
Methods: MI was induced by ligation of the coronary artery in male Wistar rats, which were separated into 3 groups; 1) the untreatment (UT) group, 2) the CO2 mist treatment (CM) group, and 3) the CO2 mist treatment+a NO synthase inhibitor, NG-nirto-L-arginine methyl ester (L-NAME) (10mg/kg/day)-administrated (CM+L) group. Rats subjected to the sham operation were used as the control (C) group. The CO2 mist was generated with a dry mist production unit, and we performed the percutaneous CO2 mist treatment for 30 min daily after MI. After 4 weeks, we assessed cardiac function by echocardiography, serum nitrate (NO3-) and vascular endothelial growth factor (VEGF) levels, and left ventricular (LV) VEGF mRNA expression.
Results: The CM group was significantly increased LV ejection fraction and decreased LV enlargement compared to the UT group (P<0.05). Furthermore, the CM group was significantly increased serum NO3- concentration compared to the UT group (P<0.01). Moreover, the CM group was significantly increased LV VEGF mRNA expression but not serum VEGF level, compared to the UT group (P<0.05). The CO2 mist-induced NO3- concentration and LV VEGF mRNA expression were significantly suppressed in the CM+L group (P<0.05). As a result, the L-NAME treatment was significantly suppressed improvement of cardiac function by the CO2 mist treatment.
In conclusion: The CO2 mist treatment could improve cardiac function after MI, via serum NO3- level and LV VEGF expression level, and these improvements were significantly abolished with L-NAME treatment. Percutaneous administered CO2 mist could induce NO activity after MI.
- © 2012 by American Heart Association, Inc.