¡¾Abstract¡¿ AIM: To observe the effects of hyperthermia (39¡æ) on the expressions of skeleton protein (¦Âª²tubulin) and heat shock protein 70 (HSP70) of cortical neurons in vitro cultured and explore the neuroprotective effect of HSP70. METHODS: The cerebral cortical neurons of embryonic mice were cultured. The cultured neurons were divided as control group which was cultured at 37¡æ and hyperthermia group which was put in high temperature (39¡æ) for 30 min. The immunofluorescence and laser scanning confocal imaging were used to detect HSP70 and ¦Âª²tubulin expressions at different time points (0, 2, 6, 24, 72 h) after hyperthermia. RESULTS: The fluorescence intensity of ¦Âª²tubulin in hyperthermia group was lower than that in control group, and it increased as recovery time went along. The fluorescence intensity of HSP70 in former group was higher than that in the latter, and it increased firstly and then decreased. The level of HSP70 reached the highest level at 2 h and remained a high level for 24 h. The expression of HSP70 was in nucleus after hyperthermia and then in cytoplasm as time went on. CONCLUSION: Hyperthermia may lead to the structural change of the cerebral cortical neuron probably through influencing skeleton protein structure. HSP70 may be involved in the protection of neurons in hyperthermia. ......