Fig. 1.
Mechanical injury depressed intracellular free calcium ([Ca2+]i) oscillations in cortical neurons. A: recording of [Ca2+]i from an individual cortical neuron using fura-2. Fura ratios (F340/F380) are plotted vs. time. Spontaneous [Ca2+]i oscillations (arrow) occur before the application of bicuculline methiodide (BMI), which produced larger amplitude oscillations. Amino-5-phosphonopentanoic acid (APV) and 1-naphthylacetyl spermine trihydrochloride (Naspm) were added sequentially to inhibit N-methyl-d-aspartate (NMDARs) and calcium-permeable α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptors (CP-AMPARs), respectively. B: recording of [Ca2+]i from an individual neuron immediately (within 10 min) following stretch-injury, 4 h post-injury (C), and 2 days post-injury (D). Spontaneous [Ca2+]i oscillations are absent from injured neurons before BMI application.