[Relationship between activation of microglia and Jaks phosphorylation induced by microwave irradiation]

To explore the relationship between microglial proinflammatory and electromagnetic radiation and unveil the role of microglia in microwave radiation induced central nervous system injury.

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.

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.

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.