Effects of domoic acid on amino acid release and intracellular free Ca~(2+) in H4 Cell

Objective To study the effect of domoic acid on amino acid release and intracellular free Ca 2+([Ca 2+]i) in H4 cell.Methods HPLC and spetroflurometer were applied to measure the contents of excitatory amino acid(EAA), inhibitory amino acid (IAA),and [Ca 2+]i in H4 cell respectively exposured to 0, 0.064, 0.640, 6.40 μmol/L domoic acid after 2h.Results Asparagic acid and Glutaminic acid: The contents of medium-dose group and high-dose group were significantly different from that of control group(P0.05);Glycine: The content of high-dose group was significantly different from that of control group(P0.05); Gamma-amino butyric acid: The contents of all dose groups were significantly different from that of control group (P0.05). EAA/IAA: The values of all dose groups were significantly higher than that of control group (P0.05) . [Ca 2+]i: The values of low-dose group, medium-dose group, and high-dose group were respectively(208.65±11.01),(342.31±15.08) and (581.36±17.24)nmol/L,increased significantly compared with (143.25±11.97)nmol/L of control group (P0.01).There were significant positive correlations(r= 0.932 0, P0.01)between the contents of EAA and that of [Ca 2+]i.Conclusion Domoic acid can cause the changes of extracellular EAA and IAA contents and intracellar [Ca 2+]i in H4 cell cultured in vitro,which may be the important mechanism of excitatory toxicity for domoic acid.