Corticotropin-Releasing Factor Antagonist Blocks Microwave-Induced Decreases in High-Affinity Choline Uptake in the Rat Brain (Rapid Communication) med./bio.

The study was performed to investigate the neural mechanism in the effect of microwaves on central cholinergic system. The aim of the experiment was to study whether corticotropin-releasing factor (CRF) is involved in the microwave induced effects on changes in "sodium-dependent high-affinity choline uptake". The specific CRF receptor antagonist (alpha-helical-CRF) was injected into the lateral cerebroventricle of rats before microwave exposure to investigate whether the irradiation induced changes in "sodium-dependent high-affinity choline uptake" in the frontal cortex and hippocampus can be blocked.

• animal
• rat/Sprague-Dawley
• whole body

Pretreatment of the rats with the CRF antagonist blocked the effect of microwaves (decrease in high-affinity choline-uptake) in the frontal cortex and the hippocampus. No significant difference in high-affinity choline-uptake was observed between the microwave- and sham-exposed animals after such treatment. The results suggest that the effects of acute low-level microwave irradiation on central cholinergic systems are mediated by corticotropin-releasing factor (CRF) in the brain. Since the CRF antagonist has no significant effect on high-affinity choline uptake in the frontal cortex and hippocampus of sham-exposed rats, this would imply that microwaves activate CRF in the brain, which in turn causes the changes in high-affinity choline uptake.