Fig. 1

Single and repeated opto-SD on periorbital mechanical allodynia in male and female mice. Periorbital thresholds were tested at 1 h, 2 days and 4 days after single SD or sham exposure (A), or 2, 4 and 14 days after the last repeated SD (B). Individual force threshold data (grams) from single SD groups for males (blue) and females (red) are shown. Opto-SD lowered periorbital mechanical thresholds (^#p < 0.0001 vs. sham). Female sex was also associated with lowered periorbital thresholds (*p = 0.011 vs. male). There were significant interactions between opto-SD and time of behavior test (^†p = 0.030) as animals recovered from opto-SD induced allodynia over time and between sex and time of behavior test (^‡p = 0.020) as females seemed to take longer to recover from opto-SD