Significance of nitrogen monoxide in the implementation of the infarctlimiting effect of remote ischemic postconditioning in myocardial ischemia-reperfusion in young and old rats

Modern medicine faces the problem of a steady growth of cardiovascular pathology. Given the high medical and social significance of the problem of treating patients with coronary heart disease and acute myocardial infarction, the search for new effective methods to prevent or mitigate ischemic myocardial damage and mechanisms for their implementation is an urgent task of modern experimental and clinical medicine. The aim of the study was to determine the significance of nitric monoxide in realizing the infarction-limiting effect of remote ischemic postconditioning (RIPostC) in myocardial ischemia-reperfusion in young and old rats. The study revealed that RIPostC has a heart attack-limiting effect in myocardial ischemia-reperfusion in both young and old rats; however, under the conditions of the systemic action of the NG-nitro-L-arginine methyl ester inhibitor at a dose of 25 mg/kg (intravenous administration 5 min before the start of reperfusion and 15 min before RIPostC), the effect remains, although not completely, in old rats but not in young rats. Apparently, the NO synthase activity and the blood level of nitric monoxide play a more significant role in the mechanisms of the cardioprotective effects of RIPostC in young rats than in old rats.

Estimation and measurement of the automobile pollution : application to Bejaia case

In this paper, we present the estimate and results of measurement of air pollution in Béjaia city in Algeria. We used an enclosure of 0,80 m3 for the collection of gases directly on the outlet side of the tailpipe of the vehicles. A three-gas detector (MX21 plus), introduced inside the enclosure, measures the rates of carbon monoxide CO, sulphur dioxide SO2 and nitric monoxide NO. We studied the exhaust pollutants according to the age of the vehicle (1980 – 2004) and the acceleration of the engine. Measurements related to a sample of 204 vehicles using gasoline or diesel oil fuel. The comparison between the rejections and the standards European, American and Japanese norms encourages us to challenge the authorities on the urgency of the introduction of the vehicle inspection and technical control. Except the new vehicles (less than 5 years old), where the results are comparable, the others exceed largely the standards. We have counted the number of vehicles passing through the Daouadji square during one month (March 2004) and calculated the total pollution rejected. The comparison with the air pollution measured in situ confirmed that urban pollution is primarily from automobile sources. On the curve of the weekly evolution of the air pollution the days and peak hours of the automobile traffic appear clearly. The correlation with the number of vehicles is very significant (0,78). By taking account of the annual rate of increase in the number of vehicles and keeping the current park without adequate maintenance, a statistical model envisages an unbearable urban pollution near 2010.