| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
|
|
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
1 Departamento de Ciencias Biologicas y Fisiologicas, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Instituto de Investigaciones de la Altura, Lima, Peru
2 School of Pharmacy and Biochemistry, University of Buenos Aires, Laboratory of Free Radical Biology, Buenos Aires, Argentina
* To whom correspondence should be addressed. E-mail: aboveris{at}ffyb.uba.ar.
Male rats exposed for 21 days to high altitude (4340 m) responded with arrest of gain weight and increased hematocrit and testosterone levels. High altitude significantly (58%) increased heart mitochondrial nitric oxide synthase (mtNOS) activity, whereas heart cytosolic eNOS and liver mtNOS were not affected. Western blot analysis found heart mitochondria reacting only with anti-iNOS antibodies, whereas the post mitochondrial fraction reacted with anti-iNOs and anti-eNOS antibodies. In vitro measured NOS activities allowed the estimation of cardiomyocite capacity for NO production, a value that increased from 57 (sea level) to 79 nmol NO/min.g heart (4340 m). The contribution of mtNOS to total cell NO production increased from 62 % (sea level) to 71 % (4340 m). Heart mtNOS activity showed a linear relationship with hematocrit and a biphasic quadratic association with estradiol and testosterone. Multivariate analysis showed that exposure to high altitude linearly associates with hematocrit and heart mtNOS activity, and that testosterone/estradiol ratio and heart weight were not linearly associated with mtNOS activity. We conclude that high altitude triggers a physiological adaptive response that up-regulates heart mtNOS activity and is associated, in an opposed manner, with the serum levels of testosterone and estradiol.
This article has been cited by other articles:
|
|
 |
|
  P. La Padula, J. Bustamante, A. Czerniczyniec, and L. E. Costa Time course of regression of the protection conferred by simulated high altitude to rat myocardium: correlation with mtNOS J Appl Physiol, September 1, 2008; 105(3): 951 - 957. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. L. Fellet, A. M. Balaszczuk, C. Arranz, J. J. Lopez-Costa, A. Boveris, and J. Bustamante Autonomic regulation of pacemaker activity: role of heart nitric oxide synthases Am J Physiol Heart Circ Physiol, September 1, 2006; 291(3): H1246 - H1254. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Navarro, R. Torrejon, M. J. Bandez, J. M. Lopez-Cepero, and A. Boveris Mitochondrial function and mitochondria-induced apoptosis in an overstimulated rat ovarian cycle Am J Physiol Endocrinol Metab, December 1, 2005; 289(6): E1101 - E1109. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
T. Zaobornyj, L. B. Valdez, P. La Padula, L. E. Costa, and A. Boveris Effect of sustained hypobaric hypoxia during maturation and aging on rat myocardium. II. mtNOS activity J Appl Physiol, June 1, 2005; 98(6): 2370 - 2375. [Abstract] [Full Text] [PDF]
|
|
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH |
| Visit Other APS Journals Online |
