[Proliferation of pulmonary fibroblasts obtained from rats with bleomycin-induced pulmonary fibrosis and effects of rat rIL-1 alpha on this proliferation].
To clarify the mechanism of pulmonary fibrosis, the growth rate of fibroblasts obtained from bleomycin (BLM)-treated rats was compared with that of fibroblasts obtained from control rats. Proliferation of fibroblasts obtained from rats at 4 days after BLM instillation (BRF) was significantly more rapid than that of fibroblasts obtained from rats at 4 days after saline instillation (CRF), as assessed by cell counting and 3H-TdR incorporation. CRF and BRF were separated by the method of discontinuous Percoll gradients. Three fibroblast fractions of specific gravity (S.G.), S.G. < 1.036, 1.036 < or = S.G. < 1.050, 1.050 < or = S.G. < 1.062, were obtained. Percentages of the densest fibroblast fraction were 46.2 +/- 5.2 in BRF and 6.4 +/- 2.8 in CRF. The densest fibroblasts in BRF proliferated more rapidly than the least dense fibroblasts. Rat rIL-1 alpha suppressed the proliferation of CRF and BRF, dose dependently. These results suggest that an increase in the densest fibroblasts in the lung might correlate with BLM-induced pulmonary fibrosis and that IL-1 alpha suppresses the proliferation of pulmonary fibroblasts.
Asada
K
K
Third Department of Internal Medicine, University of Tokushima, School of Medicine.
Ogushi
F
F
Takehara
H
H
Endo
T
T
Tani
K
K
Miki
S
S
Masuda
M
M
Ogura
T
T
D000818:Animals; D001761:Bleomycin / Q000633:toxicity*; D002455:Cell Division; D005347:Fibroblasts / Q000473:pathology; D007370:Interferon Type I / Q000494:pharmacology*; D008168:Lung / Q000473:pathology*; D008297:Male; D011658:Pulmonary Fibrosis / Q000139:chemically induced / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins
D007370:Interferon Type I; D011994:Recombinant Proteins; D001761:Bleomycin