A SIMPLE METHOD FOR THE MEASUREMENT OF THE OXYGEN CONSUMPTION AND HEART RATE OF RATS

Abstract

WHILE engaged in a study of the effect of thyroxine on the oxygen consumption and heart rate, the need arose for a simple means of measuring the oxygen consumption and heart rate of a large number of rats daily. Because existing techniques were found to be unsuitable for such studies, a simple apparatus was devised in which the only special piece of equipment required was an electrocardiogram for measuring the heart rate. This paper will describe this method and, as an example of the type of use to which it can be put, the response of the oxygen consumption and heart rate of rats to graded doses of thyroxine will be reported. Oxygen Consumption: The animal was placed in a 48 oz. jar, A, (Fig. 1) which contained soda-lime to absorb CO₂ and water. Closing the jar was a rubber stopper fitted with a T-tube, B, one arm of which led to a manometer, C,