Capillary Permeability in Adipose Tissue

A method for measurement of capillary permeability using external registration of gamma emitting isotopes after close arterial bolus injection was applied to the isolated inguinal fat pad in slightly fasting rabbits. An average extraction of 26 per cent for ⁵¹Cr-EDTA was found at a plasma flow of about 7 ml/100 g. min. This corresponds to a capillary diffusion capacity of 2.0 ml/100 g^.min which is half the value reported for vasodilated skeletal muscle having approximately twice as great capillary surface area. Thus, adipose tissue has about the same capillary permeability during slight metabolic activation as vasodilated skeletal muscle.