Varying susceptibility to myocardial infarction among C57BL/6 mice of different genetic background

Activation of the Lectin Pathway by Natural IgM in a Model of Ischemia/Reperfusion Injury

“…To address this question, mice genetically deficient in C1q were characterized in the mesenteric I/R model. Because C1q Ϫ/Ϫ mice were in the C57BL/6 genetic background and MBL Ϫ/Ϫ mice were in the 129/B6 genetic background, WT mice with a C57BL/6 genetic background were used as controls for C1q Ϫ/Ϫ mice to prevent a biased conclusion influenced by genetic background (63)(64)(65)(66). In contrast to MBL Ϫ/Ϫ mice, the injury levels in C1q Ϫ/Ϫ mice were similar to those of WT animals (pathology scores: 25 Ϯ 21% vs 22 Ϯ 17%, respectively; Fig.…”

Activation of p38 Mitogen-Activated Protein Kinase Contributes to the Early Cardiodepressant Action of Tumor Necrosis Factor

“…Colonies of mkk3 ϩ/Ϫ and mk2 ϩ/Ϫ mice were derived from these sources by crossing mkk3 Ϫ/Ϫ and mk2 Ϫ/Ϫ mice with outbred c57BL/6 mice (Harlan, Sussex, United Kingdom). To reduce background genetic variability (20), we used male mkk3 Ϫ/Ϫ and mkk3 ϩ/ϩ , as well as male mk2 Ϫ/Ϫ and mk2 ϩ/ϩ progeny of heterozygote matings, which whenever possible were litter mates. In addition, outbred male c57BL/6 mice were used to ensure that findings were not the result of within-colony idiosyncrasies (20).…”

“…To reduce background genetic variability (20), we used male mkk3 Ϫ/Ϫ and mkk3 ϩ/ϩ , as well as male mk2 Ϫ/Ϫ and mk2 ϩ/ϩ progeny of heterozygote matings, which whenever possible were litter mates. In addition, outbred male c57BL/6 mice were used to ensure that findings were not the result of within-colony idiosyncrasies (20). All gene-targeted lines were bred and maintained in the same facility under identical conditions.…”

Practical guidelines for rigor and reproducibility in preclinical and clinical studies on cardioprotection

“…Importantly, however, a reduction of infarct size by direct and remote ischemic preconditioning has been reliably demonstrated in all strains of mice tested [61]. Some transgenic or knockout strains may be on other backgrounds, in which case it is essential to use the same precise strain as the mutated mice for the WT controls, and preferably littermates [164]. …”