A switch in G protein coupling for type 1 corticotropin-releasing factor receptors promotes excitability in epileptic brains

Seizures caused by uncontrolled neuronal activity easily starts in a part of the brain called the piriform cortex. Normally, the activity of the piriform cortex is suppressed by CRF, a neuropeptide that is released in response to stress. Narla et al . found that in rats with experimentally induced epilepsy, CRF enhanced, rather than suppressed, neuronal activity in this part of the brain. In the brains of epileptic rodents, the receptor for CRF signaled through a different Gα protein, and G protein switching contributed to the CRF-induced enhancement in neuronal activity. These results may explain why stress and anxiety tend to increase the frequency of seizures in epileptics.