Fig. 9.

Results of experiment to estimate bulk-rate of anterograde axonal CTB transport. Relative fluorescence intensity (CTB injected side (Exp) relative to non-injected (Ctrl) side) is plotted versus time after unilateral intravitreal CTB injection for the ipsilateral optic nerve (a) and contralateral superior colliculus (b). Solid line through data represents results of fit to the data of the equation: Y = IF(X < X₀, Y₀,Y₀ + (Plateau – Y₀)*(1 – exp(–K*(X – X₀)))), which was used as a secondary method to determine the first time after injection that fluorescence intensity began to rise above that of the opposite-side structure (i.e., the X₀ parameter corresponding to the point that exponential growth began from baseline). For optic nerve, X₀ = 1.64 (95% CI −0.07 to 3.35); for superior colliculus, X₀ = 5.48 (95% CI 2.78 to 8.19). Error bars = SEM. N ≥ 3 rats per time point. Abbreviations: Exp = Experimental, Ctrl = Control.