Nonshivering thermogenesis in the rat. II. Measurements of blood flow with microspheres point to brown adipose tissue as the dominant site of the calorigenesis induced by noradrenaline.

摘要: Cardiac output (CO) and the fractional distribution (FD) of γ-labeled plastic microspheres (15 ± 5 μm) injected into left ventricle were used to calculate blood flow organs tissues barbital-sedated warm-acclimated (WA) or cold-acclimated (CA) white rats at rest then during their maximal calorigenic response infused noradrenaline (NA). Flow major masses brown adipose tissue (BAT) increased in WA from a mean 0.81 ml/min (0.92% CO) 13.5 ml/min (11.4% calorigenesis; it CA 2.3 ml/min (2.6% 57.2 ml/min (33.5% CO). skeletal muscle 12.0 ml/min 15.1 ml/min 9.9 ml/min 14.5 ml/min. heart muscles involved respiratory movements was two five times greater calorigenesis. most other decreased by less than 40%.Arteriovenous differences oxygen acros...