Increased expression of basic fibroblast growth factor in hyperoxic-injured mouse lung.
Basic fibroblast growth factor (bFGF) is a mitogenic polypeptide for a wide variety of cell types and has been immunolocalized in the rodent and human lung. We investigated the mRNA and protein expression of bFGF in hyperoxic-injured adult mouse lungs using northern blot analysis and immunohistochemistry. Mice (6-8 weeks) were continuously exposed to 80% oxygen up to 4 days. Levels of bFGF mRNA were increased from room air control on days 3 and 4 of hyperoxia. mRNA levels of acidic fibroblast growth factor (aFGF), fibronectin, and transin/stromelysin were also examined in this injury model. Similar to bFGF, the fibronectin and transin/stromelysin mRNA levels were increased after 3 days of hyperoxia. In contrast, the aFGF mRNA levels were gradually reduced on each day of hyperoxia. A rabbit polyclonal anti-bFGF antibody was used to determine the distribution and levels of expression in the hyperoxic-injured lungs. The room air control and day 1 hyperoxic-exposed lungs exhibited staining for bFGF in the basement membranes of the blood vessels, airways, and alveoli. Patchy but intense alveolar staining was prominent on day 4 of hyperoxia. The bFGF immunoreactivity of blood vessels and airways was unaffected by the hyperoxia exposure. These results suggest that bFGF may play a role in the alveolar response to hyperoxic-induced injury by virtue of the altered mRNA levels and protein distribution in this injury model.
Powers
M R
MR
Department of Pediatrics, Oregon Health Sciences University, Portland 97201.
Planck
S R
SR
Berger
J
J
Wall
M A
MA
Rosenbaum
J T
JT
D000818:Animals; D000906:Antibodies; D015152:Blotting, Northern; D005109:Extracellular Matrix / Q000737:chemistry; D016220:Fibroblast Growth Factor 1 / Q000235:genetics / Q000378:metabolism; D016222:Fibroblast Growth Factor 2 / Q000235:genetics / Q000378:metabolism*; D005353:Fibronectins / Q000235:genetics / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D018496:Hyperoxia / Q000276:immunology / Q000378:metabolism*; D007150:Immunohistochemistry; D008168:Lung / Q000648:ultrastructure; D019278:Matrix Metalloproteinase 3; D008666:Metalloendopeptidases / Q000235:genetics / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D012333:RNA, Messenger / Q000032:analysis; D011817:Rabbits; D051381:Rats; D012128:Respiratory Distress Syndrome / Q000276:immunology / Q000378:metabolism*
D000906:Antibodies; D005353:Fibronectins; D012333:RNA, Messenger; D016222:Fibroblast Growth Factor 2; D016220:Fibroblast Growth Factor 1; D008666:Metalloendopeptidases; D019278:Matrix Metalloproteinase 3