Noradrenergic enhancement of object recognition and object location memory in mice

Abstract

Extensive evidence indicates that noradrenergic activation is essentially involved in mediating the enhancing effects of emotional arousal on memory consolidation. Our current understanding of the neurobiological mechanisms underlying the memory-modulatory effects of the noradrenergic system is primarily based on pharmacological studies in rats, employing targeted administration of noradrenergic drugs into specific brain regions. However, the further delineation of the specific neural circuitry involved would benefit from experimental tools that are currently more readily available in mice. Previous studies have not, as yet, investigated the effect of noradrenergic enhancement of memory in mice, which show different cognitive abilities and higher endogenous arousal levels induced by a training experience compared to rats. In the present study, we investigated the effect of posttraining noradrenergic activation in male C57BL/6J mice on the consolidation of object recognition and object location memory. We found that the noradrenergic stimulant yohimbine (0.3 or 1.0 mg/kg) administered systemically immediately after an object training experience dose-dependently enhanced 24-h memory of both the identity and location of the object. Thus, these findings indicate that noradrenergic activation also enhances memory consolidation processes in mice, paving the way for a systematic investigation of the neural circuitry underlying these emotional arousal effects on memory. LAY SUMMARY: The current study successfully validated the effect of noradrenergic activation on both object recognition and object location memory in mice. This study thereby provides a fundamental proof-of-principle for the investigation of the neural circuitry underlying noradrenergic and arousal effects on long-term memory in mice.

Frontiers of stress research: the 2nd Munich Winter Conference on Stress

“…The group of Benno Roozendaal has been at the forefront of demonstrating that noradrenergic activation is essential in mediating the effects of emotional arousal on memory consolidation. Here they extend previous findings mainly from rat models to the mouse, illustrating that also in mice noradrenergic stimulation can enhance object recognition memory (Song et al, 2020). The study will pave the way for systematic investigations of the underlying neuronal circuitry, benefiting from experimental tools that are readily available in mice.…”

Effects of heterozygous deletion of autism-related gene Cullin-3 in mice

“…The times spent with objects, following extensive habituation, in our spatial/novel object recognition task were seemingly low (∼5 s); yet our findings are clearly statistically significant and differ from WT mouse behavior. Several previous studies examining spatial object recognition memory report roughly similar times spent with habituated objects [ 16 , 61 – 63 ]. Future studies are needed to confirm whether this finding is robust, reproducible, and consistent across different spatial learning and memory tasks.…”

Dopamine activity on the perceptual salience for recognition memory

“…Pharmacological activation of the noradrenergic receptors through the systemic administration of epinephrine improves recognition and memory consolidation (Dornelles et al, 2007 ). Similarly, activation of β receptors within the basolateral amygdala enhances object-in-context recognition memory (Barsegyan et al, 2014 ), NOR (Chen et al, 2022 ), and OLRM consolidation (Roozendaal et al, 2007 ; Song et al, 2021 ). The noradrenergic system presumably promotes memory consolidation due to arousal effects; since the basolateral amygdala modulates the dorsal hippocampus and insular and prelimbic cortices through the noradrenergic system (Barsegyan et al, 2019 ; Chen et al, 2022 ).…”