Fig. 5. Recovery of caffeine-induced Ca²⁺release during rest. (  A ) A second application of caffeine (Caf., 20 mm) at intervals of 1, 3, and 10 min after the offset of the previous application (  dotted line ) shows progressive recovery of transient area in three different neurons. (  B ) Proportionate recovery is comparable in control neurons and in fourth lumbar (L4) and L5 neurons after spinal nerve ligation (SNL). Two-way ANOVA shows a significant main effect for time interval, but not for injury. Groups at each data point include 4 to 14 neurons.  Error bars show SD.