Effects of betaine on the glutamate-induced neurotoxicity in primary cultured chicken brain cells

The neuroprotective effect of betaine, one of the , components of Lycii Fructus, on glutamate-induced neurotoxicity in primary cultured chicken brain cells were examined. Betaine was found to attenuate glutamate-induced neurotoxicity at the concentration of 5-10 mM in both morphological and chemical aspects. The pretreament of chicken brain cells with 5-10 mM betaine for 2 hr at the 12th day of culture before the 40 min-exposure to 500${\mu}$M glutamate significantly increased the survival rate of nerve cells in chicken brain. Betaine could also raise the decreased LDH-level due to the neurotoxicity induced with 100${\mu}$M glutamate in chicken braill cells. LDH value was decreased to 63％ of control level in chicken brain cells at the time of 48 hr after the exposure to glutamate. However, the pretreament of chicken brain cells with 5 mM betaine for 2 hr before the exposure to glutamate could prevent the decrease of LDH-level in brain cells showing 90％ of control level. Nevertheless, tile remarkable neuroprotective effect of betaine on the glutamate-inducer in neurotoxicity in cultured chicken brain cells could not be observe when betaine was simultaneously administered with glutamate.