Fig. 1
Chondroitinase ABC protects dendritic architecture following ocular hypertension. a Microbead injections produced 2–3 weeks of raised IOP; average profiles with shaded SD shown. b The AUC of IOP profiles shows a significantly greater IOP in OHT groups compared to NT UOC. Chondroitinase ABC had no effect on IOP post injection. c Cell loss was assessed by TOPRO-3 counts; example images shown. d OHT resulted in significant cell loss in the GCL compared to NT UOC; cell loss was not significantly different between OHT groups. e Dendritic morphology was assessed following DiOlistic labelling; example cells from each group shown. f Sholl profiles demonstrate that chondroitinase ABC injection in NT ABC eyes had no effect on dendritic complexity (left). OHT PBS eyes showed a reduced complexity (statistical values shown in table below plot for NT UOC against OHT PBS) that was rescued by chondroitinase ABC injection (right). Analysis of dendritic morphology revealed a significant reduction in OHT PBS retinal ganglion cells compared to in NT UOC for metrics of Sholl AUC (g), branching index (h), total dendritic length and distal dendritic length (i). j Dendritic field area was unchanged across groups, indicating reduced density of branches. k Retinal ganglion cell eccentricity had no effect on dendrite morphology, with cells analyzed across all regions (optic nerve head at x = 0, y = 0; group colors as in F-J). Multivariate regression analysis showed no significant correlation between the distance from optic disc and the outcome variables (Sholl AUC: R2 0.0018, P = 0.25; Sholl BI: R2–0.0026, P = 0.47; dendritic field area: R2 0.0993, P = 0.01, total dendritic length: R2 0.0033, P = 0.56, proximal dendritic length: R2 0.0087, P = 0.10, and distal dendritic length: R2 0.0195, P = 0.03). * = P < 0.05, ** = P < 0.01, *** = P < 0.001. Scale bars = 50 μm for (c), 100 μm for (e). For box plots, center hinge represents the mean and the upper and lower hinges represent the first and third quartiles; whiskers represent 1.5 times the interquartile range