Transcriptomics study of the prefrontal cortex in rats with recognition memory impairment induced by short-term 3.5 GHz microwave radiation

To investigate the effects of short-term 3.5 GHz microwave radiation on recognition memory and the gene expression profile of the prefrontal cortex of rats.

The behavioral performance of rats was evaluated via the novel object recognition (NOR) test, Morris water maze (MWM), and open field test (OFT) following short-term exposure to 3.5 GHz microwave radiation. Transcriptomic analysis was conducted to examine the alterations in gene expression profiles in the prefrontal cortex of rats after 6 days of 3.5 GHz microwave radiation. Key genes associated with microwave radiation induced recognition memory deficits were screened via gene interaction network analysis. The expression levels of the selected key genes were detected by real-time quantitative PCR (qPCR).

After 6 days of 3.5 GHz microwave radiation, the recognition memory of rats significantly declined (P<0.05) while their spatial learning and memory remained unchanged, and no significant anxiety - like behaviors were observed. Compared with the Sham radiation group (Sham), 1188 upregulated genes and 732 downregulated genes were detected in the prefrontal cortex of rats in the microwave radiation group (MW). Five key genes associated with microwave radiation-induced recognition memory impairment were identified by gene interaction network analysis. qPCR validation confirmed that in the prefrontal cortex, the expression levels of adrenoceptor beta 1 (Adrb1), glutamate ionotropic receptor NMDA type subunit 2b (Grin2b), Kalirin Rho guanine nucleotide exchange factor kinase (Kalrn), and myocyte enhancer factor 2c (Mef2c) were significantly upregulated (P<0.05) while that of corticotropin releasing hormone receptor 1 (Crhr1) was significantly downregulated (P<0.05).

Six days of exposure to 3.5 GHz microwave radiation can induce recognition memory impairment in rats, which may be attributed to the dysregulated gene expressions related to receptors, ion channels, and synaptic structure and function within the prefrontal cortex.