Taurine-evoked chloride current and its potentiation by intracellular Ca2+ in immature rat hippocampal CA1 neurons.
Taurine is one of the most abundant free amino acids in the immature mammalian central nervous system. In the present study, whole-cell patch-clamp recordings were made to examine taurine-evoked currents ( I(Tau)) in acutely dissociated immature rat hippocampal CA1 neurons. Taurine at low concentrations (</=1 mM) activated glycine receptors while at high concentrations (>/=3 mM) activated both glycine and GABA(A) receptors. Moreover, elevation of intracellular Ca(2+) via non-NMDA receptor activation enhanced I(Tau) reversibly. The results indicate that taurine may act as a native ligand of glycine receptors and modulate neurotransmissions in the immature hippocampus, and under certain conditions it can also activate GABA(A) receptors. The potentiation of I(Tau) by intracellular Ca(2+) may contribute to the protection effect of taurine under some cell-damaging conditions.
Wu
Z-Y
ZY
Laboratory of Receptor Pharmacology, Department of Neurobiology and Biophysics, University of Science and Technology of China, Hefei, People's Republic of China.
Xu
T-L
TL
D000818:Animals; D002118:Calcium / Q000502:physiology*; D018118:Chloride Channels / Q000502:physiology*; D006624:Hippocampus / Q000166:cytology / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D051381:Rats; D013654:Taurine / Q000502:physiology*
D018118:Chloride Channels; D013654:Taurine; D002118:Calcium