Memory Modulation by Post-training Glucose or Insulin Remains Evident at Long Retention Intervals

doi:10.1006/nlme.1996.0020

Neurobiology of Learning and Memory

Volume 65, Issue 2, March 1996, Pages 189-191

https://doi.org/10.1006/nlme.1996.0020 Get rights and content

Abstract

Immediate posttraining intraperitoneal injection of α-D[+]-glucose (30 mg/kg) facilitated, whereas a nonconvulsive dose of insulin (8 IU/kg) impaired, 24-h retention, in male Swiss mice, of a one-trial step-through inhibitory avoidance task. When mice were trained and received immediate post-training glucose or insulin injections and were tested for retention either 1 week or 1 month later, at each retention interval performance was comparable to that found with a 24-h retention interval. Thus, memory modulation by post-training administration of either glucose or insulin remain evident at long retention intervals.

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Indeed, the alteration of executive functions was not observed when 5-FU was administered with glucose, and it is shown that glucose prevented the long-term 5-FU-induced decrease of hippocampal cell proliferation. In a good agreement with our observations, it was shown that acute administration of glucose facilitates memory performances of humans with high or altered cognitive functioning (Korol, 2002) and improve learning, strategy and memory in rodents when administered systemically (Messier, 1997; Kopf and Baratti, 1996; Schroeder and Packard, 2003) or centrally (Canal et al., 2005; Dash et al., 2006; Ragozzino et al., 1996; Kopf and Baratti, 1996). Thus, our study suggests that acute glucose administration may have counteracted the deleterious impact of 5-FU alone on cognitive functions and hippocampal cell proliferation and could explain the lack of cognitive deficits with the combination 5-FU/oxaliplatin.
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Brief ReportMemory Modulation by Post-training Glucose or Insulin Remains Evident at Long Retention Intervals

Abstract

Brief Report
Memory Modulation by Post-training Glucose or Insulin Remains Evident at Long Retention Intervals