Hypertrophy of rabbit proximal tubule cells is associated with overexpression of TGF beta.
The expression of transforming growth factor beta (TGF beta) in proximal tubule cells from rabbit kidney cortex after uninephrectomy (UNX) was investigated. Cell protein and [3H]leucine incorporation in these cells were significantly increased, while cell number was decreased, at two weeks following UNX. At this time period after UNX, we found that proximal tubule cells showed a dramatic increase of cytoplasmic immunostaining with a pan-specific anti-TGF beta antibody. This was accompanied by a 3-fold increase in TGF beta 1 mRNA expression in these cells. Furthermore, proximal tubule cells from two-week uninephrectomized rabbits secrete about 2-fold higher TGF beta bioactivity to the cell conditioned medium compared to cells from sham-operated animals. Addition of anti-TGF beta 1, beta 2, beta 3 neutralizing antibody increased the growth of the former cells, and it abolished cell hypertrophy. These results indicate that hypertrophy of proximal tubule cells during compensatory renal growth is associated with overexpression of TGF beta.
Peñaranda
C
C
Research Laboratory, Fundación Jiménez Díaz, Madrid, Spain.
García-Ocaña
A
A
Sarasa
J L
JL
Esbrit
P
P
D000818:Animals; D000911:Antibodies, Monoclonal; D002478:Cells, Cultured; D015870:Gene Expression; D007124:Immunoenzyme Techniques; D007687:Kidney Tubules, Proximal / Q000166:cytology* / Q000378:metabolism; D008297:Male; D009392:Nephrectomy; D009500:Neutralization Tests; D011817:Rabbits; D016212:Transforming Growth Factor beta / Q000096:biosynthesis* / Q000235:genetics / Q000276:immunology
D000911:Antibodies, Monoclonal; D016212:Transforming Growth Factor beta