By the end of the study period (i.e., at day 180), the circulating levels of EPCs (i.e., CD31+CD117+, CD34+CD117+) were lowest in group 1 and highest in group 4, significantly higher in group 5 than those in groups 2 and 3, and significantly higher in group 3 than those in group 2, suggesting that: 1) an increase in circulating EPCs was an intrinsic response to ischemic stimulation that was suppressed by CKD; 2) ECSW treatment enhanced circulating level of EPCs. The gene discussed is PECAM1; the disease is chronic kidney disease.