SIGMAR1 and Cerebral ischemia: To further elucidate the importance of Sig-1R in macrophages on neurological functions in response to cerebral ischemia, we transferred bone marrow-derived macrophages (BMDMs) obtained from either WT or Sig-1R-/- mice to Sig-1R knockout ischemic mice 2 h after reperfusion (Figure 5A).