TY - JOUR
T1 - Altered expression of type I collagen, TGF-β1, and related genes in rat lung exposed to 85% O2
AU - Moore, A. M.
AU - Buch, S.
AU - Han, R. N.N.
AU - Freeman, B. A.
AU - Post, M.
AU - Tanswell, A. K.
PY - 1995
Y1 - 1995
N2 - The gene expressions of type I collagen and transforming growth factor- β1 (TGF-β1) were studied in lung tissue of rats exposed to air or 85% O2 for 14 days. Peak expression of type I collagen mRNA was observed by 14 days of 85% O2 exposure, at the same time as maximal immunoreactive type I collagen, which was most marked surrounding the major airways and vessels. TGF-β1 mRNA also significantly increased after 14, but not 4 or 6, days of 85% O2 exposure. TGF-β1 immunoreactivity was only detected on day 14 of 85% O2 exposure and was localized primarily to the pulmonary epithelium. As an increase in immunoreactive type I collagen was evident by day 6 of O2 exposure, the gene expressions of interstitial collagenase (MMP-1), stromelysin, and the tissue inhibitor of the metalloproteinases (TIMP) were also examined. Increased mRNA expressions of interstitial collagenase and TIMP preceded those of type I collagen and TGF-β1, occurring at 4-6 days of exposure to 85% O2, while there was no significant change in stromelysin mRNA. These findings are compatible with the initial O2-mediated increase in type I collagen deposition being a result of an altered proteinase/antiproteinase balance in the lung, and the subsequent more marked deposition being a response to increased TGF-β1 synthesis.
AB - The gene expressions of type I collagen and transforming growth factor- β1 (TGF-β1) were studied in lung tissue of rats exposed to air or 85% O2 for 14 days. Peak expression of type I collagen mRNA was observed by 14 days of 85% O2 exposure, at the same time as maximal immunoreactive type I collagen, which was most marked surrounding the major airways and vessels. TGF-β1 mRNA also significantly increased after 14, but not 4 or 6, days of 85% O2 exposure. TGF-β1 immunoreactivity was only detected on day 14 of 85% O2 exposure and was localized primarily to the pulmonary epithelium. As an increase in immunoreactive type I collagen was evident by day 6 of O2 exposure, the gene expressions of interstitial collagenase (MMP-1), stromelysin, and the tissue inhibitor of the metalloproteinases (TIMP) were also examined. Increased mRNA expressions of interstitial collagenase and TIMP preceded those of type I collagen and TGF-β1, occurring at 4-6 days of exposure to 85% O2, while there was no significant change in stromelysin mRNA. These findings are compatible with the initial O2-mediated increase in type I collagen deposition being a result of an altered proteinase/antiproteinase balance in the lung, and the subsequent more marked deposition being a response to increased TGF-β1 synthesis.
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U2 - 10.1152/ajplung.1995.268.1.l78
DO - 10.1152/ajplung.1995.268.1.l78
M3 - Article
C2 - 7840232
AN - SCOPUS:0028893163
VL - 268
SP - L78-L84
JO - American Journal of Physiology - Renal Physiology
JF - American Journal of Physiology - Renal Physiology
SN - 0363-6127
IS - 1 12-1
ER -