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

Figure 4

Entrainment and wheel-running periods of rd mice after injection of melanopsin-SAP immunotoxin. The bar below the actograms indicates the light (white) and dark (black) periods, and the light and dark periods are indicated by white and gray backgrounds, respectively. When the light/dark cycle was delayed by 8 h, (a) the rd mice in the PBS control group were capable of reentraining to the light/dark cycle, and they took 4.67 ± 0.79 days to complete the synchronization with the shifted cycle. (b) The rd mice in the 100 ng/μl group and (c) the rd mice in the 200 ng/μl group required 7.90 ± 0.55 days and 11.00 ± 0.79 days to complete the synchronization with the new light/dark cycle, respectively, indicating slower reentrainment. (d) The wild-type mice took 3.67 ± 0.29 days to complete the synchronization with the shifted cycle, and the locomotor activity of the wild-type mice was more robust than that of the rd mice. represents the day delay in the time of lights on and lights off. (e) The differences in the number of days needed for reentrainment were not statistically significant between the rd mice in the PBS control group and the wild-type group (two-way ANOVA, followed by Fisher’s LSD post hoc test, ). The number of days required for reentrainment were significantly increased in the 100 ng/μl and 200 ng/μl groups when compared with the PBS control group (two-way ANOVA, followed by Fisher’s LSD post hoc test, ). .

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