Online citations, reference lists, and bibliographies.
← Back to Search

Modulation Of Mitochondrial Nitric Oxide Synthase And Energy Expenditure In Rats During Cold Acclimation

Jorge Guillermo Peralta, Paola V. Finocchietto, Daniela Converso, Francisco Schöpfer, Marı́a Cecilia Carreras, Juan José Poderoso

Save to my Library
Download PDF
Analyze on Scholarcy Visualize in Litmaps
Share
Reduce the time it takes to create your bibliography by a factor of 10 by using the world’s favourite reference manager
Time to take this seriously.
Get Citationsy
To preserve thermoneutrality, cold exposure is followed by changes in energy expenditure and basal metabolic rate (BMR). Because nitric oxide (NO) modulates mitochondrial O2 uptake and energy levels, we analyzed cold effects (30 days at 4°C) on rat liver and skeletal muscle mitochondrial NO synthases (mtNOS) and their putative impact on BMR. Cold exposure delimited two periods: A ( days 1–10), with high systemic O2 uptake and weight loss, and B ( days 10–30), with lower O2 uptake and fat deposition. mtNOS activity and expression decreased in period A and then increased in period B by 60–100% in liver and skeletal muscle ( P< 0.05). Conversely, mitochondrial O2 uptake remained initially high in the presence of l-arginine and later fell by 30–50% ( P < 0.05). On this basis, the estimated fractional contribution of liver plus muscle to total BMR varied from 40% in period A to 25% in period B. The transitional modulation of mtNOS in rat cold acclimation could participate in adaptive responses that favor calorigenesis or conservative energy-saving mechanisms.