Cold exposure produces a large increase in rat brown adipose tissue (BAT) dopamine (DA) content. This increase is rapid (30 min of cold are sufficient to produce a maximal effect), and can be detected at different ages (from birth to adulthood). Cold also greatly increases DA turnover rate in BAT. In the same experimental conditions tyrosine hydroxylase is activated, while the activity of dopamine-beta-hydroxylase is not modified. The possibility that DA can regulate BAT functioning is discussed.