Hi,

According to sigma, you can essentially make about 60mM of L-glu i water. I have used 10-50mM stock and diluted to 10-100 uM final conc. in media or buffer of pH 7.2 for electrophysiology and other experiments. Saturating conc. will vary with the system I guess. Whether its cells or slices?  I have used glioma cells and upto 100 uM it hasnot reached saturation or almost reaching post that conc.. I have used 10-30uM as best conc. for assays with no toxicity upto 5 mins. But I guess, for inducing cytotoxicity u need to check cell survival by plotting conc. of glutamate.

In my work I required Na free L-glu to modulate Na ions as such in the buffer to see Na dependence. I guess its best to take L-glu. 

Kalpita

Hi,

Yeah Choi's papers on excitotoxicity are hallmarks. Please see them.

Hi, I used glu 10 mM in stock and 1mM-100uM in neurons cultured.

Keep in mind that more mature neurons will tolerate higher glutamate concentrations, so time in culture is important. Also keep in mind that excitotoxicity can be delayed, I can apply up to 200uM L-glut, the cells fire heavily, then stop firing, then firing returns after washout, but the cells die when returned to culture. You will likely need to titrate for your particular application.

we use 12.5 µM of NMDA and 100 µM glutamate in our cultures of mouse neurons

Dear All,

I am want to screen my compounds for rescue against Glutamate induced excocitotoxicity on rat primary cortical neurons. I referred few papers suggesting glutamate exposure for 24 hrs, however, few papers suggest acute exposure like 30 min. or 50 min. with high concentration of Glutamate. Can some one suggest me the suitable concentration as well as exposure time which may help in screening my molecules?

try first on a 24h period and if you get a good toxicity with 100 µM glutamate you may thus test a time course: 30 min, 60 min, 1, 2, 6, h to test the optimal period of treatment under your conditions. If you use high amounts of glutamate, such as 5 or 10 mM, as tested by some authors, you may possibly kill your cell by an other mechanism such as inhibition of transporter xc-, which exchange glutamate against cysteine, thus leading to an oxidative shock (so called oxytosis).

I do agree with Duval. I used 100 uM to induce at least 50% toxicity (death of cortical cultured neuron) in 12DIV culture (Article Hyper-insulinemia increases the glutamate-excitotoxicity in ...

We use 100 um for 24hrs on mature neurons, for neuroprotective studies. This gave us the best results.