OBJECTIVETo observe the neurologic damage in rat hippocampus after electromagnetic field (EMF) acute or chronic irradiation and research the protective effects of Chinese medicine diet (CMD) which comprised ferulic acid, ginsenoside, astragalus polysaccharide and rhodiola sachalinensis.

METHODSEighty rats were divided into ten groups (n = 8): normal diet with shame irradiation group (NS), normal diet with chronic irradiation group (NCI), three groups of normal diet with acute irradiation after 3 h, 24 h, 72 h (NAI), Chinese medicine diet with shame irradiation group (CS), Chinese medicine diet with chronic irradiation group (CCI), three groups of Chinese medicine diet with acute irradiation after 3 h, 24 h, 72 h (CAI). The chronic EMF irradiation were performed by electromagnetic wave at 15 W/cm2 for 20 min everyday for 8 weeks continuously. The acute EMF irradiation were performed by electromagnetic wave at 65 W/cm2 for 20 min after feeding with CMD for 8 weeks. The learning and memory were evaluated by Morris water maze before/after electromagnetic wave irradiation. The apoptotic cells in hippocampus was detected by Tunel staining. The peroxidation damage of EMF and the protective effect of CMD intervention were assayed by measuring superoxide dismutase (SOD), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and reactive oxygen species (ROS).

RESULTSThe acute and chronic EMF irradiation disturbed the ability of learning and memory significantly (P < 0.05), CMD intervention markedly antagonized this effect. The apoptotic cells in hippocampus increased evidently after EMF irradiation (P < 0.05), but CMD intervention reduced the apoptotic cells. The acute and chronic EMF irradiation induced the oxidative stress by down-regulating SOD activity, GSH-Px activity, ROS inhibiting and up-regulating the content of MDA obviously (P < 0.05), and CMD intervention reduced peroxidation damage significantly (P < 0.05).

CONCLUSIONThe acute and chronic EMF irradiation could initiate neurologic damage in hippocampus. CMD intervention has protective effect on the impaired learning and memory, the neuron apoptosis, the peroxidation damage induced by EMF irradiation. CMD intervention plays a significant protective role in antagonizing neurologic damage in the later stage of acute irradiation and chronic irradiation.