Fig. 3. Infarct sizes (IS) and Troponin concentrations in Adora2b bone marrow chimeric mice. Bone marrow (BM) chimeric mice for the Adora2b were subjected to 60 min of myocardial ischemia (MI) and 120 min of reperfusion (A–C ). ISs are presented as percentage of the area at risk (AAR). The absence of the adenosine receptor A2b (Adora2b) on bone marrow derived cells led to IS of 60 ± 4%[Adora2b^−/−(KO)^BM→ WT (wild-type)] and 63 ± 4%[Adora2b^−/−(KO)^BM→ Adora2b^−/−]. Adora2b presence on bone marrow derived cells led to IS of 42 ± 2% (WT^BM→ WT) and 48 ± 1%[WT^BM→ Adora2b^−/−(KO)] (A ). Measurement of serum troponin I concentrations by enzyme-linked immunosorbent assay (ELISA). Adora2b absence on bone marrow derived cells increased troponin I values to 122 ± 8 ng/ml [Adora2b^−/−(KO)^BM→ WT] and 92 ± 11 ng/ml [Adora2b^−/−(KO )^BM→ Adora2b^−/−(KO)]. Adora2b presence on bone marrow derived cells reduced troponin I values to 22 ± 4 ng/ml (WT^BM→ WT) and 34 ± 13 ng/ml [WT^BM→ Adora2b^−/−(KO)] (B ). ISs were measured by double staining with Evans blue and triphenyltetrazolium chloride. ISs are expressed as the percentage of the AAR that underwent infarction (C ). Representative images of ISs from the experiments in A and B are displayed (mean ± SD; n = 5 per group). KO = knockout.