Mitochondrial and cytosolic CBD (1 μm) responses in naive cultures loaded with Rhod-FF, AM and fura-2 AM. A, B, Sample traces from neurons showing delayed cytosolic (black trace) and early biphasic mitochondrial (gray trace) Ca2+ responses. NMDA application was used as an indicator of neuronal viability and to make a clear distinction between neurons and glia. C, Application of FCCP (1 μm) led to a drop in mitochondrial Ca2+ levels and prevented a further Ca2+ rise by CBD. Vertical lines have been added to visualize the order of responses. All Rhod-FF data are raw fluorescence values (OD, optic density), and fura-2 AM responses are presented as ratio values.