Direct implication of carbon monoxide in the development of heart failure in rats with cardiac hypertrophy subjected to air pollution.
Pollution is known to particularly affect patients with respiratory insufficiency and right ventricle abnormalities. We therefore hypothesized that carbon monoxide (CO) at low dose could be involved in cardiovascular disorders in patients with chronic hypoxic pulmonary hypertension secondary to chronic hypoxia. Ten-week-old male and female healthy Dark Agouti rats were randomly divided into two series--untrained (U) and trained (T)--of four groups of 18 animals each. Both U and T series were continuously exposed to ambient air (U(AIR), and T(AIR); n = 16) or air plus 50 ppm CO (U(AIR+CO) and T(AIR+CO); n = 18). Similarly, rats initially subjected to right ventricle hypertrophy secondary to chronic hypoxia (H) were continuously exposed to ambient air (TH(AIR), and UH(AIR); n = 18) or air plus 50 ppm CO (UH(AIR+CO), and TH(AIR+CO); n = 18). Doppler-echocardiography and hemodynamic studies performed at rest both indi-cated that CO had no significant effect on cardiac morphology or functions in control rats (U(AIR+CO) vs U(AIR)). In contrast, cardiac dilation and large decreases in left ventricular ejection fraction, mitral early diastolic rapid inflow (E) deceleration, E/atrial contraction filling (A) ratio, +dP/dt, and -dP/dt were found in TH(AIR+CO) compared with TH(AIR). After exposure, heart rate variability was unaffected in U(AIR+CO), whereas total power spectra were markedly decreased and low frequency/high frequency power ratio was increased in TH(AIR+CO) rats. CO pollution could be directly involved in cardiac disorders of patients with pre-existent hypertrophic cardiomyopathies.
Melin
Alexandre
A
Laboratoire de Physiopathologie de la Paroi Artérielle, Faculté de Médecine, Tours, France.
Bonnet
Pierre
P
Eder
Veronique
V
Antier
Daniel
D
Obert
Philippe
P
Fauchier
Laurent
L
D000395:Air Pollutants, Occupational / Q000633:toxicity*; D000397:Air Pollution / Q000009:adverse effects*; D000818:Animals; D002248:Carbon Monoxide / Q000633:toxicity*; D006332:Cardiomegaly / Q000139:chemically induced / Q000503:physiopathology*; D015150:Echocardiography, Doppler; D005260:Female; D006333:Heart Failure / Q000139:chemically induced*; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects; D009929:Organ Size / Q000187:drug effects; D010805:Physical Conditioning, Animal / Q000502:physiology; D051381:Rats; D020257:Ventricular Remodeling / Q000187:drug effects / Q000502:physiology
D000395:Air Pollutants, Occupational; D002248:Carbon Monoxide