Zambon NJ, Nagle R, Pokala V, Gibbs RB, Johnson DA (2001) Low dose 192 IgG-saporin selectively destroys basal forebrain cholinergic neurons and impairs acquisition of a spatial memory task. Neuroscience 2001 Abstracts 534.13. Society for Neuroscience, San Diego, CA.
Summary: We previously showed that a high dose (1 μg) of the selective cholinergic immunotoxin 192 IgG-saporin (SAP), injected into the medial septum (MS) of Sprague-Dawley rats, impeded acquisition of a delayed matching-to-position (DMP) spatial memory task, whereas injections of ibotenate (5 μg in 1 μL) did not. The present study examined the effects of lower doses of SAP (0.22 and 0.45 μg in 1 μl) on DMP acquisition. Animals received either SAP or vehicle injected directly into the MS. Two weeks later, animals were food deprived and trained to the DMP task. Rats received 8 trial pairs/day until they reached a criterion of 15/16 correct choices. Seven days later, post-criteria testing for retention was performed. Brain tissues were analyzed for choline acetyltransferase (ChAT) activity, or were processed for immunohistochemical detection of ChAT and parvalbumin. Control rats required significantly fewer days (13.1) to reach criterion than rats that received 0.22 (22.0 days) or 0.45 (20.1 days) μg SAP. There was no effect of SAP treatment on post-criteria testing. Injections of SAP produced marked depletion of ChAT-positive cells and ChAT activity, but no apparent depletion of parvalbumin staining in the MS. In contrast, ibotenate injections used in the previous study were shown to produce marked depletion of parvalbumin staining in the MS, but no significant cognitive impairment. The data suggest that selective destruction of cholinergic neurons in the MS significantly impairs acquisition of the DMP task.
Related Products: 192-IgG-SAP (Cat. #IT-01)