Mouse Brain c‐fos mRNA Distribution Following a Single Electroconvulsive Shock

: The regional distribution of c‐fos mRNA in the mouse brain has been investigated by in situ hybridization autoradiography after seizures induced by an acute electroconvulsive shock (ECS). ECS led to a widespread induction of the proto‐oncogene c‐fos in the brain, with highest concentrations in discrete areas within the limbic system and also in the hypothalamus and cerebellum. The mild stress of sham treatment in earclipped animals induced a weaker and qualitatively different pattern of c‐fos mRNA expression involving the cortex, hippocampus, and cerebellum. These data suggest the usefulness of c‐fos in situ hybridization as a marker of neuronal stimulation and in mapping a range of effects from a mild stress to the robust changes of an electroconvulsive seizure.