Neurotoxicity and neuroprotection assays.

Different concentrations of glutamate (A: top) and quinolinic acid (A: bottom) were used to induce excitotoxic cell death in astrocytes, which were quantified by measuring LDH release after 24 hours. Protein levels were also calculated using the Bradford assay to standardise the cell numbers within each well. Significance *p<0.05 compared to control (n = 3 for each treatment group). (B: top) Level of LDH release after 24 hrs when astrocytes were incubated with 500 µM of glutamate and varying concentrations of different selective NMDAR antagonists. Employing two-tailed t-test analyses showed that all treatment groups of MK-801 and memantine, even at concentrations of 0.1 µM resulted in reduced LDH levels in the supernatant. Significance */⁰ p<0.05 compared to control (n = 3 for each treatment group). (B: bottom) Level of LDH release after 24 hrs when astrocytes were incubated with 500 nM of QUIN and varying concentrations of different selective NMDAR antagonists. Using two-tailed t-test analyses revealed that all MK-801 treatment groups resulted in reduced LDH production but only memantine concentrations above 0.5 µM were statistically significant in decreasing LDH levels. Significance */⁰ p<0.05 compared to control (n = 3 for each treatment group).