Objective To explore the effects of exercise on dentate gyrus (DG) neLuogenesis and the ability of learning and memory in hippocampus-lesioned adult rats.Methods Hippocampus lesion was produced by intrahippocampal microinjection of kainic acid (KA).Bromodeoxyuridine (BrdU) was used to label dividing cells.Y mae test was used to evaluate the ability of learning and memory.Exercise was conducted in the form of forced running in a motor-driven running wheel.The speed of wheel revolution was regulated at 3 kinds of intensity:lightly running, modemtely running,or heavily running.Resutts Hippocampus lesion could increase the number of BrdU-labeled DG cells,moderately running after lesion could further enhance the number of BrdU-laheled cells and decrease the error number (EN) in Y maze test,while neither lightly running,nor heavily running had such effects.There was a negative conelation beiween the numberof DG BrdU-labeled cells and the EN in the Y maze test after running.Condusion Moderate exercise could enhance the DG neurogenesis and ameliorate the ability of learning and memory in hippocampus-lesioned rats.