I am having problems with Ca2+ imaging (with Fura 2AM)of Cortical neurons in culture. They are not giving any [Ca2+]i response to any of the agonists tested. In my previous lab i worked with hippocampal neurons and astrocytes. Neurons used to respond well to glutamate receptor agonists and P2 agonists but here surprisingly they didn't show any response upon KCl depolarization and no response to Thapsigargin treatment. I have checked with fresh agonists, changed the buffer etc.. but they seem to be adamant to any stimuli. Responded only to Ca2+ ionophore.
Can any one help me figure out where the problem is???