Inert gas diffusion method for measurement of blood flow. Comparision of bolus injection to directly measured blood flow in the isolated gastrocnemius muscle.

The isolated cat gastrocnemius preparation was used to study the relation between the washout of Xenon measured by external monitoring and blood flow measured directly by a dropcounter. The experimental possibility was thereby tested of recording the total tracer bolus and its subsequent washout by external monitoring, using the height H and the corresponding area A of the washout curve. The partition coefficient A, and the amount of recirculation were evaluated in separate experiments. According to Zierler, the blood flow per gram of tissue should equal A. • H/A. This relation was verified experimentally. Exponential analysis was carried out but the results of it were not considered to support the hypothesis of a two compartment inparallel model in skeletal muscle. The shape of the washout curve did not suggest the existence of A-V shunts. ADDITIONAL