Selective immunotoxic lesions of basal forebrain cholinergic cells: Effects on learning and memory in rats.

Abstract

Male Long-Evans rats were given injections of either 192 IgG-saporin, an apparently selective toxin for basal forebrain cholinergic neurons (LES), or vehicle (CON) into either the medial septum and vertical limb of the diagonal band (MS/VDB) or bilaterally into the nucleus basalis magnocellularis and substantia innominata (nBM/SI). Place discrimination in the Morris water maze assessed spatial learning, and a trial-unique matching-to-place task in the water maze assessed memory for place information over varying delays. MS/VDB-LES and nBM/SI-LES rats were not impaired relative to CON rats in acquisition of the place discrimination, but were mildly impaired relative to CON rats in performance of the memory task even at the shortest delay, suggesting a nonmnemonic deficit. These results contrast with effects of less selective lesions, which have been taken to support a role for basal forebrain cholinergic neurons in learning and memory.

Aversive stimulus attenuates impairment of acquisition in a delayed match to position T-maze task caused by a selective lesion of septo-hippocampal cholinergic projections

“…For example, Dornan et al [16] reported that a selective reduction of cholinergic transmission in the basal forebrain was by itself insufficient to account for the functional impairments in spatial learning of rats using a Morris water maze (MWM) paradigm. Baxter et al [4,5], also utilizing a MWM task, reported similar findings.…”

Spatial reference and working memory across the lifespan of male Fischer 344 rats

“…Spatial working memory (delayed match-to-place) task-One week following completion of the reference memory task, young (n=17), middle-aged (n=29), and aged (n=21) rats were trained on a delayed-match-to-place version of the water maze (adapted from Baxter et al, 1995) to assess the effects of age on spatial working memory and to determine whether age-related deficits observed in reference memory generalized across spatial tasks. Over twelve consecutive days, rats received two trials a day with varying inter-trial intervals.…”

“…In the current study, young, middle-aged, and aged F344 rats were tested sequentially on a spatial reference memory and a delayed-match-to-place (working memory) version of the water maze (adapted from [4]). The reference memory task was used to determine the age of onset of mnemonic deficits and whether reliable individual differences in performance could be observed during aging.…”

Lifelong environmental enrichment in rats: impact on emotional behavior, spatial memory vividness, and cholinergic neurons over the lifespan

“…Alteration of the cholinergic system originating in the MS/vDBB has been implicated in the age-related spatial memory impairments (Aubert et al 1995;Baskerville et al 2006;Sugaya et al 1998). This view was challenged as selective cholinergic lesions of the septal region did not affect water maze performance or produced only modest alterations (e.g., Baxter et al 1995). The persistence of a spatial memory, however, may be compromised when such lesions also affect the NBM (Parent and Baxter 2004;Traissard et al 2007).…”