[Effect of ambient temperature on metabolism and heart rate of resting albino rats].

Heart rate and oxygen consumption were measured simultaneously in albino rats. These measurements were carried out in the resting animal at different temperatures between 18 degrees and 33 degrees C. The metabolism evolution with the environmental temperature allowed to place the thermal neutrality at 29 degrees C. The resting heart rate varies as metabolism. It shows the lowest values round the thermoneutrality and increases quickly as the environment is cooling. This result shows the effect of the thermal environment upon the resting heart rate level. On the other hand, the non linear relationship between metabolism and heart rate points out that the heart rate increase is not the only factor that allows an increased oxygen consumption during the body temperature regulation.