Noradrenaline thermogenesis in conscious and anaesthetised pouched mice (Saccostomus campestris)

1. The metabolic response to injections of noradrenaline (NA) and saline (control) was investigated in conscious and anaesthetised (sodium pentobarbitone) pouched mice, Saccostomus campestris. 2. NA injection produced a calorigenic response which was significantly greater than that elicited by saline injection in both conscious and anaesthetised animals. 3. This calorigenic response was enhanced by motor activity in conscious pouched mice, but the exclusion of measurements recorded during visible activity eliminated the influence of movement. 4. Anaesthetised pouched mice underwent mild Hypothermia and displayed a retarded metabolic response to NA injection which suggests that anaesthesia affects the expression of NA-induced thermogenesis. 5. The validity of proposed techniques for the measurement of NA thermogenesis is further discussed.