Aim:To study the protective effects of compound FLZ,a novel synthetic ana-logue of natural squamosamide,on learning and memory impairment and lesionsof the hippocampus caused by icv injection of β-amyloid_(25-35)(Aβ_(25-35))in mice.Methods:Mice were icv injected with the Aβ_(25-35)(15 nmol/mouse),and thentreated with oral administration of 75 mg/kg or 150 mg/kg of FLZ once daily for 16consecutive days.The impairment of learning and memory in mice were testedusing step-down test and Morris water maze test.The content of malondialdehyde(MDA)and the expressions of acetylcholinesterase(ACHE),Bax,and Bcl-2 in theCA1 region of the mouse hippocampus were measured by biochemical and immu-nohistochemical analysis,respectively.The pathological damages of hippocam-pus were observed using a microscope.Results:FLZ(75 mg/kg,150 mg/kg)significantly attenuated Aβ_(25-35)-induced impairment of learning and memory in thestep-down test and Morris water maze test.FLZ also reduced pathological dam-ages to the hippocampus induced by Aβ_(25-35)Furthermore,FLZ prevented theincrease of AChE and Bax,and the decrease of Bcl-2 immunoreactive cells in theCA1 region of the hippocampus,and reduced the increase of MDA content in thehippocampus in mice injected with Aβ_(25-35).Conclusion:FLZ has protective ac-tion against the impairment of learning and memory and pathological damage tothe hippocampus induced by icv injection of Aβ_(25-35)in mice. Aim: To study the protective effects of compound FLZ, a novel synthetic ana-logue of natural squamosamide, on learning and memory impairment and lesions of the hippocampus caused by icv injection of β-amyloid_ (25-35) (Aβ_ (25-35) ) in mice. Methods: Mice were icv injected with the Aβ_ (25-35) (15 nmol / mouse), and thentreated with oral administration of 75 mg / kg or 150 mg / kg of FLZ once daily for 16 consecutive days. The of learning and memory in mice were tested using a step-down test and Morris water maze test. The content of malondialdehyde (MDA) and the expressions of acetylcholinesterase (ACHE), Bax, and Bcl-2 in the CA1 region of the mouse hippocampus were measured by Results: FLZ (75 mg / kg, 150 mg / kg) significantly attenuated Aβ_ (25-35) -induced impairment of learning and biochemical and immu-nohistochemical analysis, respectively.The pathological damages of hippocam-pus were observed using a microscope memory in thestep-down test and Morris water maze test. FLZ also reduced pathological dam-ages to the hippocampus induced by Aβ_ (25-35) Furthermore, FLZ prevented the increase of AChE and Bax, and the decrease of Bcl-2 immunoreactive cells in the CA1 region of the hippocampus, and reduced the increase of MDA content in thehippocampus in mice injected with Aβ_ (25-35). Conflusion: FLZ has protective ac-tion against the impairment of learning and memory and pathological damage tothe hippocampus induced by icv injection of Aβ_ (25-35) in mice.