Passage of albumin from plasma to suction skin blisters.

To study the transvascular passage of albumin from the plasma to the skin interstitium, suction blisters were developed on the abdominal skin of six young, healthy male volunteers. Fifteen minutes after the blisters had been formed and the suction had been stopped, 125I-albumin was injected intravenously and the disappearance of the tracer protein from plasma was compared to its appearance in blister fluid as a function of time for up to 4 h after the injection. There was a linear increase of blister fluid activity with time after injection and the mean accumulation rate of the six subjects was 0.9 +/- 0.4 (SD)%/h. It is suggested that this figure is a representative measure of the leakage of albumin through the skin microvasculature. In previous studies, a ten-fold higher accumulation rate of albumin was found when the protein tracer was administered intravenously before the suction was induced. This difference was probably due to a suction-induced increase of the filtration gradient across the skin vessels. It is concluded that both methods might be used to obtain a comparative measure of the local rate at which albumin passes from plasma to the interstitial fluid of the skin.