Relationship between activation of microglia and Jaks phosphorylation induced by microwave irradiation / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To explore the relationship between microglial proinflammatory and electromagnetic radiation and unveil the role of microglia in microwave radiation induced central nervous system injury.</p><p><b>METHODS</b>N9 microglia cells cultured in vitro were exposed to microwave at 90 mW/cm2. Cell flow cytometry was used to observe the expression of CD11b at different time points after exposure; ELISA was used to detect the concentration of TNF-alpha in N9 cell culture supernatant; RT-PCR analysis confirmed iNOS mRNA expression in N9 microglia cells; and Nitrate Reductase Method was used to test NO amount in culture supernatant.</p><p><b>RESULTS</b>The CD11b positive microglial cells increased significantly at 3 h after microwave exposure (P < 0.05), continued to increase until 24 h and peaked at 6 h after exposure. The amount of TNF-alpha rose dramatically from 1 h to 24 h after exposure (P < 0.01) and peaked at 3 h [(762.1 +/- 61.5) pg/ml] after exposure (P < 0.01). The level of NO started to increase at 1 h [(4.48-0.59) micromol/L] and lasted for 24 h after exposure. The expression of iNOS mRNA increased significantly at 1 h (P < 0.05), and tripled the original expression at 6 h after exposure, hereafter, it decreased slightly, but all were higher than the control group within 24 h after exposure.</p><p><b>CONCLUSION</b>Microwave radiation could induce the activation of microglia cells. The activated microglia cells could induce microglial proinflammatory by producing large amounts of TNF-alpha, NO, etc.</p>

Effects of occupational microwave irradiation on heat shock protein 70 expressions in rat hippocampus / 中华劳动卫生职业病杂志

<p><b>OBJECTIVE</b>To study the change of heat shock protein (HSP)70 expression after exposure to occupational microwave in rats hippocampus, and explore the role of HSP70 in the mechanism of bio-effect of microwave irradiation.</p><p><b>METHODS</b>The animal model was established by whole body exposures in 90, 5 W/cm(2) microwave irradiation field for 20 min in rats. Changes of the mRNA of hsp70 expressions in rat hippocampus at different time were studied by RT-PCR, and the protein change by Western blot.</p><p><b>RESULTS</b>The mRNA and protein expression of hsp70 in rat hippocampus increased after 90 W/cm(2) and 5 W/cm(2) microwave irradiation for 20 min. The anal temperature and the value of SAR increased significantly. These changes were positively correlated with power and irradiation time of microwave. The results indicated that microwave irradiation led to HSP70 syntheses effectively.</p><p><b>CONCLUSION</b>Microwave irradiation can obviously induce the thermal effect and activate HSP70, and initiate the endogenous protective mechanism of central nervous system.</p>