Regulation of Reentrainment Function Is Dependent on a Certain Minimal Number of Intact Functional ipRGCs in rd Mice

Figure 2

Intravitreal injection of melanopsin-SAP led to partial ablation of ipRGCs in a dose-dependent manner. (a) Immunohistochemically labeled ipRGCs using antibodies against melanopsin and comparison of the number of ipRGCs on flat-mounted retina following intravitreal injection of immunotoxin melanopsin-SAP in rd mice. (A–C) The number of ipRGCs per visual field (200x magnification) on flat-mounted retinas in different dose groups; (D–F) the results of the control eyes (PBS injection group). As the dose of melanopsin-SAP increased, the number of melanopsin-positive cells in the experimental eye decreased, while that in the control eye remained the same. Bar = 250 μm. (b) Analysis of the survival rate of ipRGCs after immunotoxin injection. The ipRGC survival rate was defined as (ipRGC number of experimental eye)/(ipRGC number of control eye) × 100%. The survival rate of ipRGCs was significantly reduced in the 200 ng/μl and 400 ng/μl groups when compared with the 100 ng/μl group (one-way ANOVA with Tukey’s multiple comparison test, ). But the difference between the 200 ng/μl group and the 400 ng/μl group was not statistically significant (one-way ANOVA with Tukey’s multiple comparison test, ). .

(a)

(b)