The brain's record of experience: kindling-induced enlargement of the active zone in hippocampal perforated synapses

• Published in: Brain research Vol. 513; no. 1; p. 175
• Main Authors: Geinisman, Y, deToledo-Morrell, L, Morrell, F
• Format: Journal Article
• Language: English
• Published: Netherlands 09-04-1990
• Subjects: Animals; Electric Stimulation; Hippocampus - physiology; Hippocampus - ultrastructure; Kindling, Neurologic; Microscopy, Electron; Neuronal Plasticity; Rats; Synapses - physiology; Synapses - ultrastructure
• ISSN: 0006-8993
• DOI: 10.1016/0006-8993(90)91107-R

Kindling is a consequence of intermittent electrical stimulation of a local forebrain area leading to a durable augmentation of synaptic responsiveness in the stimulated circuit. The basis for this functional change is unknown, but there is evidence suggesting that it entails a structural modification of synapses. The present report demonstrates that hippocampal kindling induces a selective enlargement of active zones in perforated axospinous synapses formed by stimulated axons. Since the active zone is the site of intracellular transmission, its enlargement involving only a certain subpopulation of synapses provides a likely structural substrate of synaptic plasticity associated with kindling.