Temporal changes in mRNA expression for bikunin in the kidneys of rats during calcium oxalate nephrolithiasis.
Inter-alpha-inhibitor and other bikunin-containing proteins are synthesized in relatively large quantities by the liver. These proteins function as Kunitz-type serine protease inhibitors and appear capable of inhibiting calcium oxalate (CaOx) crystallization in vitro. Preliminary studies have shown that renal tubular epithelial cells synthesize bikunin in response to CaOx challenge. To examine this response in vivo, a sensitive reverse transcription-quantitative competitive template-PCR was developed to detect and quantify poly(A)+ -tailed bikunin mRNA expression in kidney tissue from normal rats and rats developing CaOx nephrolithiasis after challenge with ethylene glycol. Bikunin mRNA expression in rat liver tissue was assessed as a positive control. The expression of bikunin mRNA in liver did not differ significantly between normal control rats and experimental rats with induced hyperoxaluria and renal CaOx crystallization. In contrast, there were significant temporal increases in the levels of bikunin mRNA expression in rat kidneys during CaOx nephrolithiasis after challenge with ethylene glycol. Urinary excretion of bikunin-containing proteins seemed to increase concomitantly. These findings indicate an association between the induction of hyperoxaluria/CaOx nephrolithiasis and the expression of the bikunin gene in rat kidneys.
Iida
S
S
Department of Pathology and Laboratory Medicine, University of Florida College of Medicine, Gainesville 32610, USA.
Peck
A B
AB
Johnson-Tardieu
J
J
Moriyama
M
M
Glenton
P A
PA
Byer
K J
KJ
Khan
S R
SR
D000510:Alpha-Globulins / Q000096:biosynthesis; D000818:Animals; D001483:Base Sequence / Q000235:genetics; D002129:Calcium Oxalate / Q000378:metabolism*; D003460:Crystallization; D018076:DNA, Complementary / Q000235:genetics; D006023:Glycoproteins / Q000235:genetics* / Q000652:urine; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D007669:Kidney Calculi / Q000378:metabolism* / Q000473:pathology / Q000652:urine; D008297:Male; D008562:Membrane Glycoproteins; D008969:Molecular Sequence Data; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012016:Reference Values; D013997:Time Factors; D014360:Trypsin Inhibitor, Kunitz Soybean
D000510:Alpha-Globulins; D018076:DNA, Complementary; D006023:Glycoproteins; D008562:Membrane Glycoproteins; D012333:RNA, Messenger; C109148:SPINT2 protein, human; D002129:Calcium Oxalate; C011877:inter-alpha-inhibitor; D014360:Trypsin Inhibitor, Kunitz Soybean