ABSTRACT
<p><b>OBJECTIVE</b>To investigate the effects of microwave irradiation on the expression and regulation of heat shock proteins (HSPs) in primary cultured rat hippocampal neurons.</p><p><b>METHODS</b>Neurons were exposed to 90 mW/cm(2) microwave irradiation for 10 minutes. Western blot was used to determine the expression of HSP27, HSP70, HSP90 and heat shock factor 1 (HSF1) at 0, 3, 6, 12 and 24 hour respectively. Real-time RT-PCR was used to determine the mRNA expression of HSF1. DNA-binding activity of HSF1 was measured by electrophoretic mobility shift assay (EMSA).</p><p><b>RESULTS</b>The protein expression of HSP27 was significantly increased by 22%, 36%, 18% at 3, 6, 12 h, respectively (P < 0.05). The protein expression of HSP70 was significantly increased by 23%, 32%, 26% at 3, 6, 12 h, respectively (P < 0.05, P < 0.01). The protein expression of HSP90 was significantly increased by 27%, 33% at 6, 12 h, respectively (P < 0.05, P < 0.01). The DNA-binding activity of HSF1 was stimulated, however, no significant change of the expression of HSF1 was observed on both the mRNA and protein levels.</p><p><b>CONCLUSION</b>The transcriptional activity of HSF1 is activated by microwave irradiation, which promotes the expression of HSPs. Heat shock response which contributes to establish a cytoprotective state is induced by microwave irradiation in primary cultured rat hippocampal neurons.</p>
Subject(s)
Animals , Rats , Cells, Cultured , Heat-Shock Proteins , Metabolism , Hippocampus , Metabolism , Radiation Effects , Microwaves , Neurons , MetabolismABSTRACT
<p><b>OBJECTIVE</b>To investigate the effect of low intensity and very high frequency (VHF) electromagnetic radiation (170 MHz) on nervous system function and serum enzymes and immune function in human subjects with occupational exposure to VHF.</p><p><b>METHODS</b>To measure the intensity of VHF and other environmental factors on the spot, to hold the questionnaire about chief complaints, to examine the rheoencephalography and the neurobehavior function, to analyze ALT, AST, ALP and LDH, and IgA, IgM and IgG in experimental group and control group.</p><p><b>RESULTS</b>The intensity of VHF (direction of antenna: 0 degrees, 10 m and 135 degrees, 20 m) was higher than that of national standard on-the-spot. The incidences of symptoms such as headache, insomnia and amnesia etc. was significantly higher in experimental group (P < 0.01). Rheoencephalography indicated that the raising time of both left [(0.155 3 +/- 0.057 9) s] and right [(0.154 1 +/- 0.059 2) s] in the experimental group after exposure were significantly longer than before exposure [(0.104 4 +/- 0.030 2) s, (0.103 2 +/- 0.030 4) s respectively] or in the control [(0.118 5 +/- 0.056 8) s, (0.117 7 +/- 0.057 5) s respectively, (P < 0.01)]. Neurobehavior function test showed that digital symbol, digital span and pursuit aiming test were decreased after exposure in the experimental group (P < 0.01). Serum enzyme analysis showed that AST, ALP and LDH were significantly increased after exposure in the experimental group (P < 0.01). No marked change was found in IgA level, while the levels of IgM and IgG after exposure in the experimental group especially the latter were significantly increased (P < 0.01).</p><p><b>CONCLUSIONS</b>Low-intensity VHF radiation can decrease the nervous system function in occupationally exposed personnel and induce increase in some kinds of enzymes and immunoglobulins.</p>
Subject(s)
Adolescent , Adult , Humans , Male , Electroencephalography , Radiation Effects , Electromagnetic Fields , Higher Nervous Activity , Immunoglobulin G , Blood , Radiation Effects , Immunoglobulin M , Blood , Radiation Effects , Occupational Exposure , Radiation Dosage , Radio Waves , T-Lymphocyte Subsets , Allergy and Immunology , Radiation EffectsABSTRACT
Objective To investigate the effects of electromagnetic irradiation on activation of protein kinase C(PKC)and phosphorylation of glutamate receptor 2(GluR2)in rat cerebellum.Methods Sixty male Wistar rats were divided randomly into a control group and an electromagnetic exposure group(including 5 subgroups ob- served at different time points after the irradiation,eg.0 hour,3 hours,12 hours,24 hours and 72 hours after irradi- ation),with 10 rats in each group.All the rats in the exposure group were exposed to 90 mW/cm2 electromagnetic ir- radiation for 20 minutes,their rectal temperature was detected immediately after irradiation and the specific absorption rate(SAR)value was calculated,activation of PKC was detected with improved TaKai method,the level of cerebellar GluR2 expression and phosphorylation(ser880)was detected by using Western blot.Results Immediately(0 hour)after exposure,the rectal temperature of rats increased 2.99℃,SAR value was 8.66 W/kg.When compared to the control group,it was found that there was no significant difference between the exposure group and the control group with regard to all the parameters at 3,12,24 and 72 hours after exposure,except that the cerebellar PKC acti- vation and GluR2(ser 880)phosphorylation decreased significantly immediately after irradiation.Conclusion The electromagnetic irradiation has injurious effects on cerebellar signal pathway of for motor learning.