Localization of cyclophilin A and cyclophilin C mRNA in murine kidney using RT-PCR.
Cyclosporin A (CsA), which is widely used as an immunosuppressant, has a nephrotoxic side effect. The mechanism of this nephrotoxicity is not well understood; however, recent studies suggest that cyclophilin (cyp) is responsible for mediating the immunosuppressive action of CsA through the interaction with the Ca(2+)- and calmodulin-dependent phosphatase, calcineurin. While cyp A mRNA is expressed ubiquitously, cyp C mRNA has been shown to be topically expressed, including in the kidney. We examined: (1) distribution of cyp A and cyp C mRNA in microdissected murine nephron segments, using a combination of reverse transcription and polymerase chain reaction (RT-PCR) techniques, and (2) the effect of CsA administration on cyp C mRNA expression in proximal convoluted tubule. Among the nephron segments examined, large signals for cyp C PCR product were detected in proximal convoluted tubule and proximal straight tubule. Our data showed that the distribution of cyp C mRNA was uneven, and it mainly existed in segments that are relatively sensitive to CsA toxicity. In contrast, cyp A mRNA was found to be distributed almost equally along the nephron segments examined. By CsA administration, the signal for cyp C mRNA PCR product was increased. These results suggest that cyp C may play some role in the renal tubular disorder observed in CsA nephrotoxicity.
Otsuka
M
M
Second Department of Internal Medicine, Tokyo Medical and Dental University, Japan.
Terada
Y
Y
Yang
T
T
Nonoguchi
H
H
Tomita
K
K
Marumo
F
F
D000591:Amino Acid Isomerases / Q000032:analysis* / Q000378:metabolism; D000818:Animals; D001483:Base Sequence; D015139:Blotting, Southern; D002352:Carrier Proteins / Q000032:analysis* / Q000378:metabolism; D000072622:Cyclophilin C; D021983:Cyclophilins; D003524:Cyclosporins / Q000032:analysis / Q000494:pharmacology; D017931:DNA Primers; D007274:Injections, Intraperitoneal; D007684:Kidney Tubules / Q000737:chemistry* / Q000187:drug effects; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D008969:Molecular Sequence Data; D019696:Peptidylprolyl Isomerase; D016133:Polymerase Chain Reaction / Q000379:methods; D012333:RNA, Messenger / Q000032:analysis* / Q000378:metabolism; D014158:Transcription, Genetic
D002352:Carrier Proteins; D003524:Cyclosporins; D017931:DNA Primers; D012333:RNA, Messenger; D000591:Amino Acid Isomerases; D021983:Cyclophilins; D000072622:Cyclophilin C; D019696:Peptidylprolyl Isomerase