A mutated exon 14 with a TGT to TCC mutation resulting in a Cys674Ser substitution and an FRT flanked neo cassette in intron 14 were inserted via homologous recombination. Flp mediated recombination removed the neo cassette. This mutation removes half of the key thiol that is a target of ischemia induced S-glutathiolation. The presence of the C674S allele was confirmed by sequencing of both genomic DNA and cDNA from cardiac endothelial cells.