A New Neuromodulatory Action of Taurine: Long-Lasting Increase of Synaptic Potentials
The physiological role of taurine, one of the most abundant free amino acids in the mammalian brain, is still poorly understood. A solid body of electrophysiological studies has demonstrated that taurine application causes neuroinhibitory actions in different regions of the CNS. In this sense, taurine has been shown to reduce the spontaneous neuronal firing, to hyperpolarize the resting membrane potential, to diminish the membrane input resistance and to increase the membrane Cl- conductance in different CNS neurons2, 4, 7, 19, 23, 24. On the basis of these observations, taurine has been proposed as a putative neuroinhibitory transmitter in the CNS. However, because of the lack of selective taurine antagonists, this possibility has not been unambiguously demonstrated so far. In fact, many of the taurine-in-duced neuroinhibitory effects have been shown to be blocked by GABA and/or glycine receptor antagonists4, 7, 20.
KeywordsSynaptic Response Synaptic Potential Synaptic Efficacy fEPSP Slope Nerve Terminals21
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