Fig. 4

Splenectomy removes the protective effect of RIPC on ischemic brain injury. Splenectomy was conducted 1 day before 40 min RIPC and 90 min MCAO. Non-splenectomy animals underwent anesthesia and surgical exposure of the spleen without removal. a Experimental protocols. Three groups of animals were prepared: MCAO, RIPC + MCAO, and splenectomy + RIPC + MCAO (n = 18 per group). b Representative TTC images of animals from each group, n = 8 per group. The infarct areas are outlined with blue lines. c Brain water content of contralateral and ipsilateral hemispheres from each rat was detected through the wet-dry method. The calculating formula is BWC = [(wet weight) − (dry weight)/wet weight] × 100%, n = 4 per group. d Cerebral blood flow during the MCAO was measured at three time points: baseline, ischemia, and reperfusion. Data are normalized to baseline and expressed as percentages. e Body weight of all rats from each group was measured over the 7 days after MCAO. f–h Neurological function and sensorimotor behaviors were assessed by neurological deficit score, beam balance score, and foot fault index, n = 6 rats per group. Data are presented as means ± SEM, *p < 0.05, **p < 0.01 versus MCAO group. ^#p < 0.05, ^##p < 0.01 versus RIPC + MCAO rats