The frequency range of electroacupuncture in treatment of Alzheimer's disease in rats is commonly 2-5 Hz (low frequency) and 50-100 Hz (high frequency). We established a rat model of Alzheimer's disease by injecting β-amyloid 1-42 (Aβ1-42) into the bilateral hippocampal dentate gyrus to verify which frequency may be better suited in treatment. Electroacupuncture at 2 Hz or 50 Hz was used to stimulate Baihui (DU20) and Shenshu (BL23) acupoints. The water maze test and electrophysiological studies demonstrated that spatial memory ability was apparently improved, and the ranges of long-term potentiation and long-term depression were increased in Alzheimer's disease rats after electroacupuncture treatment. Moreover, the effects of electroacupuncture at 50 Hz were better than that at 2 Hz. These findings suggest that high-frequency electroacupuncture may enhance hippocampal synaptic transmission and potentially improve memory disorders in Alzheimer's disease rats.
Keywords: Alzheimer's disease; Baihui (DU20); Shenshu (BL23); electroacupuncture; frequency; learning and memory; long-term depression; long-term potentiation; nerve regeneration; neural regeneration.