The DHEAS-Induced Enhancement of Hippocampal Primed Burst Potentiation is Blocked by Psychological Stress
LTP, memory, neural plasticity, neurosteroids, psychological stress, rat
Digital Object Identifier (DOI)
This series of studies investigated the effects of psychological stress and the neurosteroid dehydroepiandrosterone sulfate (DHEAS) on hippocampal primed burst (PB) and long-term (LTP) potentiation, two electrophysiological models of memory. The DHEAS and stress manipulations were performed on awake rats, and then PB and LTP were recorded while the rats were anesthetized. DHEAS enhanced PB potentiation when administered to rats under non-stress conditions, but had no effect when given to stressed rats. Further study showed that DHEAS enhanced PB potentiation only when it was administered before, but not after, the rats were stressed. The DHEAS and stress manipulations had no effect on LTP.
This study provides three major findings regarding stress, neurosteroids and hippocampal plasticity. First, DHEAS enhanced a threshold form of plasticity (PB potentiation), but had no effect on a supra-threshold form of plasticity (LTP). Second, stress blocked the DHEAS-induced enhancement of PB potentiation. Third, stress and DHEAS effects on the hippocampus were so durable they could be performed on awake animals and then be studied while the animals were anesthetized. That DHEAS enhanced a subset of forms of hippocampal plasticity under restricted behavioral conditions may help to resolve conflicting observations of DHEAS effects on cognition and mood in people.
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Citation / Publisher Attribution
The International Journal on the Biology of Stress, v. 3, issue 2, p. 107-121
Scholar Commons Citation
Diamond, David M.; Fleshner, Monika; and Rose, Gregory M., "The DHEAS-Induced Enhancement of Hippocampal Primed Burst Potentiation is Blocked by Psychological Stress" (1999). Psychology Faculty Publications. 1313.