Lung water is increased in regions of higher neutrophil retention
following acute bead embolization.
Tsang, John, and Brad Brush.
U.B.C. Pulmonary Research Laboratory, St. Paul's Hospital, 1081
Burrard Street, Vancouver, B.C. Canada. V6Z 1Y6
APStracts 3:0010A, 1996.
Previous reports have shown that neutrophils are retained in the lung
after acute embolization and that these neutrophils play an important
role in the subsequent formation of permeability pulmonary edema. The
present study was designed to test the hypothesis that acute embolic
injury results in microvascular damage in lung regions with the
greater retention of neutrophils. Seventeen pigs (20 +/- 2 kg) were
embolized by injecting polystyrene beads (250 [mu]; labelled with
131I) into the right atrium over 5 minutes. Five pigs, which received
no embolic beads, served as control. Neutrophils (89 +/- 5% pure),
isolated on Ficoll-Histopaque gradient, were radiolabelled with
111Indium oxine. Twenty minutes after embolization, the radiolabelled
neutrophils were injected into the right atrium along with 85Sr
microspheres to mark the initial neutrophil distribution within the
lung as well as the regional pulmonary blood flow at the time of
their delivery. The animals were sacrificed 50 minutes after
embolization and the lungs were removed, frozen over liquid nitrogen
and cut into 60 samples. The data show that following embolization,
regional neutrophil retention was inversely related to the regional
blood flow but was not affected by the embolic load in the same
region. Regional extravascular lung water was increased in regions of
higher neutrophil retention but the regions with increased edema did
not receive a greater embolic load. These results show that
microvascular injury occurs in the lung regions with the greatest
neutrophil retention and that this increased retention of neutrophils
is unrelated to the extent of embolization.
Received 22 June 1995; accepted in final form 22 December 1995.
APS Manuscript Number A679-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 22 January 96