Effect of acclimation temperature on the concentration of the mitochondrial ‘uncoupling’ protein measured by radioimmunoassay in mouse brown adipose tissue

Abstract

The effect of acclimation temperature on the concentration of the mitochondrial ‘uncoupling’ protein (M _r 32 000) from brown adipose tissue of mice has been investigated. The uncoupling protein was measured by a specific radioimmunoassay. Between 33°C (thermoneutrality) and −2°C there was a progressive increase with decreasing environmental temperature in the amount of uncoupling protein. For mice at −2°C the mitochondrial concentration of the protein was 9-times higher than at 33°C, while the total amount of the protein in interscapulaar brown adipose tissue was estimated to be nearly 80-times greater at −2°C compared to 33°C.