Entorhinal cortex lesioning protects hippocampal CA3 neurons from stress-induced damage.

The role of the entorhinal cortex (EC) in stress-induced damage in terms of dendritic branching points and intersections of hippocampal CA3 neurons has been investigated. Following bilateral electrolytic lesions of the EC, the rats were subjected to restraint stress, 6 h per day for 21 days. Chronic restraint stress resulted in the atrophy of hippocampal CA3 neurons and the lesioning of the EC prior to stress significantly (P < 0.001) reduced this dendritic atrophy. These results show that the neuronal vulnerability to chronic stress can be attenuated by entorhinal glutamatergic denervation.