The Effect of Subacute Supplementation of Taurine on Spatial Learning and Memory

Abstract

Abstract:Although the effect of taurine on the heart and liver is well studied, there has been no direct observation concerning the effect of taurine on spatial learning and memory at the behavior level. In this study, we tested the effect of subacute taurine supplementation with evaluation by the Morris water maze method. Although swim distance to find the platform of taurine-supplemented rats was significantly longer than that of control rats due to increase of swimming velocity, escape latency and the efficacy of learning and memory was comparable in both groups. These results suggest that taurine supplemented orally does not affect the learning and memory function. Taurine, 2-aminoethylsulfonic acid, is widely distributed throughout the body including the liver and heart. The roles of endogenous taurine in the liver and heart are to increase bile acid secretion by forming bile acid conjugate [2] and regulate Ca 2+ kinetics to protect and improve the heart function [17], respectively. In the brain, taurine is also abundant, especially in the hippocampus, and modulates synaptic transmission as an inhibitory neuromodulator interacting with g-aminobutyric acid type A (GABA A ) or glycine receptors [9,22]. Recent electrophysiological studies using rat brain preparations, however, have shown that taurine application induced long-lasting synaptic potentiation [3,6]. The features of this taurine-induced synaptic potentiation are similar to those of long-term potentiation (LTP) [4,19], which is a typical example of synaptic plasticity, and is thought to be a basic model for learning and memory [8], indicating that taurine is likely to be involved in learning and memory. Despite accumulation of findings on the relationship between taurine and synaptic plasticity by electrophysiological studies, the effect of taurine on learning and memory at the behavior level is complicated. Studies of acute administration of taurine indicate that it has no effect on humans [1,20] and mice [15], whereas studies investigating the subacute or chronic effect of taurine, often taken exogenously in food supplements on a daily basis, are still controversial. Sanberg and Fibiger reported that taurine impaired memory functions [16]. On the other hand, El Idrissi reported that taurine improved learning and retention in aged mice [5]. In these conflicting studies, the passive avoidance test was adopted to -Note-

P4‐159: Taurine in drinking water recovers learning and memory in the adult APP/PS1 mouse model of Alzheimer's disease

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Effect of an Energy Drink on Physical and Cognitive Performance in Trained Cyclists

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