Molecular identification of the liver- and the heart-type fatty acid-binding proteins in human and rat kidney. Use of the reverse transcriptase polymerase chain reaction

The cDNAs of two types of fatty acid-binding protein (FABP) present in human kidney, previously described as types A and B, were isolated using reverse transcriptase-PCR (RT-PCR) with human kidney mRNA and various sets of primers. The cDNA fragments were cloned and sequenced. Renal FABP type A and B cDNAs appeared to be completely identical to human liver- and heart-type FABP cDNAs respectively. In the second part of this study we demonstrated the presence of liver-type FABP in rat kidney by chromatography, e.l.i.s.a. and immunocytochemistry. The ratio and cellular distribution of the two FABP types varies markedly in human and rat kidney. Using RT-PCR we were also able to prepare and identify liver- and heart-type FABP cDNAs with mRNA from both male and female rat kidney.