Reactive plasticity in the dentate gyrus following bilateral entorhinal cortex lesions in cynomolgus monkeys

摘要: Hippocampal structural plasticity induced by entorhinal cortex (EC) lesions has been studied extensively in the rat, but little comparable research conducted primates. In current study we assessed long-term effects of bilateral aspiration EC on multiple markers circuit organization hippocampal dentate gyrus young adult monkeys (Macaca fascicularis). Alternate histological sections were processed for visualization somatostatin and vesicular acetylcholine transporter (VAChT) immunoreactivity acetylcholinesterase histochemistry (AChE). The revealed distinct laminar circuitry stereology-based morphometric quantification. Consistent with findings rats, volume somatostatin-immunopositive outer molecular layer (OML), innervated projections from EC, was decreased 42% relative to control values. inner (IML) displayed a corresponding volumetric expansion response denervation OML as measured AChE staining, not when visualized quantification VAChT immunoreactivity. Nonetheless, stereological estimation 36% increase total length VAChT-positive cholinergic fibers IML after damage, along no change OML. Together, these suggest that despite substantial species differences circuitry, capacity reactive following previously documented is at least partly conserved primate gyrus. J. Comp. Neurol. 500:192–201, 2007. © 2007 Wiley-Liss, Inc.