Mitochondrial nitric oxide metabolism during rat heart adaptation to high altitude: effect of sildenafil, L-NAME and L-arginine treatments

ZAOBORNYJ T; VALDEZ LB; IGLESIAS DE; GASCO M; GONZALES G; BOVERIS A

AMERICAN JOURNAL OF PHYSIOLOGY-HEART AND CIRCULATORY PHYSIOLOGY

AMER PHYSIOLOGICAL SOC

Lugar: Bethesda MD; Año: 2009 vol. 296 p. 1741 - 1747

0363-6135

Rats submitted to high altitude (Cerro de Pasco, Perú, 4,340 m, Po(2) = 12.2 kPa) for up to 84 days showed a physiological adaptive response with decreased body weight gain (15%), increased right ventricle weight (100%), and increased hematocrit (40%) compared with sea level animals. These classical parameters of adaptation to high altitude were accompanied by an increase in heart mitochondrial enzymes: complexes I-III activity by 34% and mitochondrial nitric oxide synthase (mtNOS) activity and expression by >75%. The hyperbolic increase for mtNOS activity during adaptation to high altitude was similar to the observed pattern for hematocrit. Hematocrit and mtNOS activity mean values correlated linearly (r(2) = 0.75, P