[Expressions of TNF alpha, PDGF in alveolar type II epithelial cells of rats with bleomycin-induced pulmonary fibrosis].
OBJECTIVE
The expressions of TNF alpha and PDGF in alveolar type II epithelial cells of rats with bleomycin(BLM)-induced pulmonary fibrosis were studied.


METHODS
A single intratracheal injection of BLM was administrated to induce pulmonary fibrosis of rats. Animals were killed at day 3,7,14 and 28 after BLM-administration. The immunohistochemical methods were used to analyze the expressions of TNF alpha and PDGF proteins in alveolar epithelium of rats. The total RNA was extracted from the alveolar type II epithelial cells of rats and the expressions of TNF alpha and PDGF mRNA were analyzed with Northern blot.


RESULTS
TNF alpha and PDGF were expressed in the alveolar type II epithelial cells of BLM-administrated rats. The expression of TNF alpha elevated in median and late-stage of the process and reached the peak at day 28. While the expression of PDGF elevated in early-stage and reached the peak at day 7. By contrast, TNF alpha and PDGF weren't expressed in the alveolar type II epithelial cells of normal controls.


CONCLUSIONS
The results show that the alveolar type II epithelial cell from rats with pulmonary fibrosis overexpresses TNF alpha and PDGF and they may play roles in the pathogenesis of lung fibrosis.
Song
M
M
Division of Respiratory Medicine, First Hospital of Beijign Medical University, Beijing 100034.
He
B
B
Qiu
Z
Z
D000818:Animals; D001761:Bleomycin; D004847:Epithelial Cells / Q000378:metabolism; D008297:Male; D010982:Platelet-Derived Growth Factor / Q000096:biosynthesis* / Q000235:genetics; D011650:Pulmonary Alveoli / Q000473:pathology; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000378:metabolism*; D012333:RNA, Messenger / Q000096:biosynthesis / Q000235:genetics; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis* / Q000235:genetics
D010982:Platelet-Derived Growth Factor; D012333:RNA, Messenger; D014409:Tumor Necrosis Factor-alpha; D001761:Bleomycin