Performance factors in regard to impaired memory and tolerance induced by atropine sulfate

Kasckow, John; Thomas, Garth J.; Herndon, Robert M.

doi:10.3758/bf03332176

Cited by 12 publications

(3 citation statements)

References 14 publications

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“…Wainer, Levey, Rye, Mesulam, and Mufson (1985), by double staining (immunocytochemical localization of choline acetyltransferase reactivity combined with retrograde transport of horseradish peroxidase), have established that the septohippocampal pathway is only about 50% cholinergic. Nonetheless, performance of the representational memory-dependent task has been found to be very sensitive to anticholinergic drugs such as scopolamine and atropine (Brito, Davis, Stopp, & Stanton, 1983; Kasckow, Thomas, & Herndon, 1984; Messer, Thomas, & Hoss, 1983; Ordy, Thomas, & Dunlap, 1982), and, in contrast, performance on a dispositional memory-dependent task is relatively insensitive to scopolamine (Brito et al, 1983).…”

Section: Effects Of Posterior Septal Lesionsmentioning

confidence: 99%

Differential effects of posterior septal lesions on dispositional and representational memory.

Thomas¹,

Gash²

1986

Behavioral Neuroscience

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A distinction between two classes of memory has been made in terms of the sensory availability of cues at the time of making discriminations which are influenced by past experience. Three tasks objectively defining this distinction were learned in a T-maze by three groups of rats: a delayed nonmatching-to-sample (DNMTS) which depends on representational memory; a simple sensory discrimination (SD) which depends on dispositional memory; and a more difficult discrimination, which also depends on dispositional memory, called the simultaneous conditional discrimination (SCD). The DNMTS and SD tasks were acquired quickly; the SCD task took many more trials. Posterior septal lesions impaired DNMTS performance but had no effect on retention of either the conditional discrimination (SCD) or the simple sensory discrimination (SD) tasks which depend on dispositional memory. The present study provides further evidence that dispositional and representational memory systems have at least partially distinct anatomical substrates in the brain and that it is the representational and not the conditional aspects of the DNMTS task that are impaired by the septal lesions.

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Section: Effects Of Posterior Septal Lesionsmentioning

confidence: 99%

Differential effects of posterior septal lesions on dispositional and representational memory.

Thomas¹,

Gash²

1986

Behavioral Neuroscience

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“…Biochemical and behavioral studies indicate that the sensitivity of systems mediated by muscarinic acetylcholine (ACh) receptors respond to the level of neurotransmitter activity. Thus, chronic treatment with muscarinic antagonists results in impaired performance on memory tasks, and tolerance develops following initial exposures to the drug (Kasckow et al, 1984;Messer et al, 1987). A molecular basis for this phenomenon was suggested by the evidence that muscarinic receptor levels can be regulated by their own activity and that this regulation appears to be by a negative-feedback process.…”

mentioning

confidence: 99%

Regulation of muscarinic receptors in hippocampus following cholinergic denervation and reinnervation by septal and striatal transplants

Joyce

Gibbs

et al. 1989

J. Neurosci.

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The regulation of hippocampal muscarinic M1 and M2 receptors was studied by autoradiographic methods following cholinergic denervation and reinnervation from embryonic septal transplant. In young adult male rats the density of M1 sites, labeled either with 3H-pirenzepine (PZ) or 3H-N-methylscopolamine (NMS, in the presence of excess carbachol), exceeded by 4- to 5-fold the density of M2 sites, labeled with 3H-NMS in the presence of excess PZ. Both receptors appeared to be densest in hippocampal regions lowest in acetylcholinesterase or 3H-hemicholinium-3 binding. The distribution of M1 receptors did differ from the distribution of M2 receptors within subregions of the hippocampus. Along the mediolateral axis from the subiculum to the lateral CA 1, the density of M1 receptors is uniform, but the density of M2 receptors decreases. Also apparent is the relatively small difference in density between the CA1 and dentate gyrus for M1 receptors but a significantly greater difference for M2 receptors. However, the response of M1 and M2 receptors to long-term cholinergic denervation following fimbriafornix transection of the septal cholinergic input and to cholinergic innervation by embryonic septal transplants was similar. Long-term denervation (40-60 d) resulted in a 30-60% increase in both M1 and M2 receptors within regions of the hippocampal formation. Receptor levels were reduced to normal in regions innervated by septal transplants. For both receptors, the changes in the density of sites were due to alterations in the Bmax and not the Kd for the radioligands. The specificity of this regulation is supported by the evidence that (1) the degree and topography of the normalization of muscarinic receptor density was entirely dependent on the degree and pattern of cholinergic reinnervation by the fibers of the septal transplant, (2) cholinergic fiber reinnervation by embryonic striatal grafts also down-regulated the density of M1 and M2 receptors, and (3) successfully surviving transplants (e.g., cerebellar and striatal) that did not provide innervation to the hippocampus did not induce down-regulation of muscarinic receptors. Changes in the density of sites were not related to changes in the width of the hippocampus following denervation and reinnervation. The data support the view that the majority of M1 and M2 receptors are located postsynaptically on neurons within the hippocampus and not presynaptically on cholinergic fibers.

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“…1The intention was to reduce congestion in the trachea and lungs. Given the presence of the enzyme atropine esterase in the rat, a dose of 10 mg/kg should be used (see Kasckow, Thomas, & Herndon, 1984). …”

mentioning

confidence: 99%

Mammillothalamic tracts and representational memory.

Thomas¹,

Gash²

1985

Behavioral Neuroscience

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The mammillothalamic tracts, which connect the mammillary bodies of the brain stem with the anterior thalamic nuclei of the forebrain, are an integral segment of Papez's circuit and have long been considered to be involved in mediation of emotional aspects of behavior. This study showed that a complete transection of these tracts substantially impairs the ability for rats to perform discriminations that depend on representational memory but not those that depend on dispositional memory. Nor were there any marked alterations in the emotional domain of behavior.

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Performance factors in regard to impaired memory and tolerance induced by atropine sulfate

Cited by 12 publications

References 14 publications

Differential effects of posterior septal lesions on dispositional and representational memory.

Differential effects of posterior septal lesions on dispositional and representational memory.

Regulation of muscarinic receptors in hippocampus following cholinergic denervation and reinnervation by septal and striatal transplants

Mammillothalamic tracts and representational memory.

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