Altered steady-state levels of mRNA coding for extracellular matrices in renal tissues of ddY mice, an animal model for IgA nephropathy.
Correlations between the steady-state mRNA levels of extracellular matrices using specific cDNA probes for the alpha 1 chain of type IV collagen (alpha 1 (IV) chain); laminin A, B1, and B2 chains; and heparan sulfate proteoglycan (HSPG); and glomerular injuries in ddY mice were evaluated. Eight-, sixteen- and forty-week-old ddY mice were used in this study. ICR mice of the same age served as control. Extracted total RNA of pooled kidneys was fixed on a filter and then hybridized with the cDNA probes. Renal cryostat sections were incubated with rabbit anti-mouse type IV collagen, laminin, and HSPG antisera and then stained with FITC-labeled goat anti-rabbit IgG antiserum. The sections were also stained with FITC-labeled goat anti-mouse IgA, IgM, IgG, and C3 antisera. In light microscopy, the average number of glomerular cells was calculated at each age. Increased expression of extracellular matrices genes for the alpha 1(IV) chain; laminin A, B1, and B2 chains; and HSPG was found in renal tissues of ddY mice. Staining of type IV collagen, laminin, and HSPG was observed in renal tissues of ddY mice at each age. Increased proteinuria in 40-week-old ddY mice might be related to the decrease in glomerular basement membrane HSPG which acts as the anionic sites in such areas. Marked proliferation and or expansion of glomerular cells and mesangial matrices were observed in 40 week-old-ddY mice. The intensity of IgA and C3 deposits in the glomeruli was parallel to the levels of mRNA for such components.(ABSTRACT TRUNCATED AT 250 WORDS)
Tomino
Y
Y
Department of Medicine, School of Medicine, Juntendo University, Tokyo, Japan.
Nakamura
T
T
Ebihara
I
I
Funabiki
K
K
Yaguchi
Y
Y
Shimizu
M
M
Shirato
I
I
Koide
H
H
D000818:Animals; D003176:Complement C3 / Q000378:metabolism; D004195:Disease Models, Animal; D005109:Extracellular Matrix / Q000378:metabolism*; D005455:Fluorescent Antibody Technique; D005922:Glomerulonephritis, IGA / Q000276:immunology / Q000378:metabolism* / Q000473:pathology; D007136:Immunoglobulins / Q000378:metabolism; D007668:Kidney / Q000473:pathology; D051379:Mice; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism*
D003176:Complement C3; D007136:Immunoglobulins; D012333:RNA, Messenger