Fig. 4. Growth cone collapse after washing out 1 mm tetracaine. (A ) Dorsal root ganglion neurons (DRG), (B ) retinal ganglion cell layer neurons (RET), and (C ) lumbar sympathetic chain neurons (SYMP). One-way analysis of variance for repeated measurements indicated that the growth cone collapse trend after 10-min exposure to tetracaine was significantly different from that after the 60-min exposure in all three neuronal types (P < 0.01). Also, the trend after 60-min exposure to 1 mm tetracaine was significantly different from that after 60-min exposure to vehicle solution in all three neuronal types (P < 0.01). In the sympathetic neurons, the trend after 10-min exposure to 1 mm tetracaine was significantly different from that after 10-min exposure to vehicle solution (P < 0.01). *Significantly different from the value of the corresponding vehicle exposed neurons (P < 0.01). †Significantly different from the growth cone collapse percentage immediately after exposure to 1 mm tetracaine for 60 min (P < 0.01). ¶Significantly different from the growth cone collapse percentage immediately after exposure to 1 mm tetracaine for 10 min (P < 0.01). The “pre” in the horizontal scale indicates the time point immediately before exposure to tetracaine; the “post-exp” indicates the time-point immediately before the washing out of tetracaine. Horizontal scale is not time scale. Values are mean ± SD.