LPA increases glia proliferation and decreases neurite sprouting in zebrafish after SCI. Five days after SCI in the GFAP:GFP line, BrdU-positive glial cells proliferate at the central canal and accumulate at the edges of the lesion site (A) compared with LPA-treated fish (B). GFAP expression at the edges of lesion in control fish (C) compared with more abundant GFAP expression in LPA-treated animals (D). E: Quantitation of BrdU-positive cells reveals an increase with LPA treatment. Results are given as mean ± SEM (n = 10 in each group). *P < 0.001 by two-tailed t-test, 95% confidence). F: Three weeks after SCI, the Islet1:GFP line shows a significant decrease in neurite number at the lesion site in LPA-treated fish compared with controls (Con). Results are given as mean ± SEM (n = 8 for each genotype). ***P < 0.001 by two-tailed t-test, 95% confidence). G: Neurite sprouting in the islet1:EGFP line around the lesion site in control treatment compared with reduced neurite number from both sides of the lesion site in LPA treatment. H: Locomotor recovery assays show motor function 3 weeks after SCI (n = 7 animals from each group) NS, not significant. Scale bars: 100 μm (A, B, and G); 50 μm (C and D).