Apoptosis in microvascular endothelial cells of perfused rabbit lungs with acute hydrostatic edema.
We test the hypothesis that microvascular endothelial cells may undergo apoptosis in response to acute pulmonary venous hypertension. The isolated rabbit lungs were perfused in situ for 4 h with left atrial pressure of 0, 10, or 20 mmHg at a constant blood flow. Edema formation was monitored by lung weight gain. To assay for apoptosis, we performed agarose gel electrophoresis of DNA, in situ nick end labeling of DNA strand breaks, and electron microscopy. We also examined the levels of expression of Bcl-2, a suppressor of apoptosis, in microvascular endothelial cells using an immunohistochemical technique. In a vascular pressure-dependent fashion, we found apoptosis in endothelial cells of alveolar septal capillaries, as well as expression of Bcl-2 in arteriolar and venular endothelial cells. We conclude that acute pulmonary venous hypertension induces apoptosis in capillary endothelial cells but not in arteriolar and venular endothelial cells, suggesting that microvascular endothelial cell apoptosis is dependent on the levels of Bcl-2 expression and influences the formation or resolution of acute hydrostatic lung edema.
Gotoh
N
N
Second Department of Internal Medicine, Gifu University School of Medicine, Gifu 500, Japan.
Kambara
K
K
Jiang
X W
XW
Ohno
M
M
Emura
S
S
Fujiwara
T
T
Fujiwara
H
H
D000208:Acute Disease; D000818:Animals; D017209:Apoptosis; D004730:Endothelium, Vascular / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D005786:Gene Expression Regulation; D006801:Humans; D006874:Hydrostatic Pressure / Q000009:adverse effects; D007150:Immunohistochemistry; D020287:In Situ Nick-End Labeling; D066298:In Vitro Techniques; D008168:Lung / Q000098:blood supply / Q000473:pathology / Q000503:physiopathology*; D008297:Male; D009929:Organ Size; D010477:Perfusion; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000032:analysis / Q000235:genetics; D011654:Pulmonary Edema / Q000209:etiology / Q000473:pathology / Q000503:physiopathology*; D011817:Rabbits; D012039:Regional Blood Flow; D014655:Vascular Resistance
D019253:Proto-Oncogene Proteins c-bcl-2