The members of the solute carrier family 9 (SLC9) belong to the Na+/H+ exchanger (NHE) family, which are involved in a wide array of essential cellular processes including control of cellular volume and intracellular pH. SLC9A2/NHE2 is widely distributed in human tissues including those of the intestine, colon, stomach, skeletal muscles, kidney, and blood-brain barrier (BBB) in the brain. SLC9A2/NHE2 is suggested to participate in the formation of edema during ischemic stroke by increasing sodium transportation through the BBB. In addition, the recovery of intestinal barrier function damaged by ischemic injury is impaired in slc9a2 deficient mice.