We developed an automated squint assay using both black C57BL/6J and white CD1 mice to measure the interpalpebral fissure area between the upper and lower eyelids as an objective quantification of pain. The automated software detected a squint response to the commonly used nociceptive stimulus formalin in C57BL/6J mice. After this validation, we used the automated assay to detect a dose-dependent squint response to a migraine trigger, the neuropeptide calcitonin gene–related peptide, including a response in female mice at a dose below detection by the manual grimace scale. Finally, we found that the calcitonin gene–related peptide amylin induced squinting behavior in female mice, but not males. These data demonstrate that an automated squint assay can be used as an objective, real-time, continuous-scale measure of pain that provides higher precision and real-time analysis compared with manual grimace assessments.

我们开发了一种自动斜视测定法，使用黑色 C57BL/6J 和白色 CD1 小鼠来测量上眼睑和下眼睑之间的睑间裂面积，作为疼痛的客观量化。自动化软件检测到 C57BL/6J 小鼠对常用伤害性刺激福尔马林的斜视反应。经过验证后，我们使用自动测定来检测偏头痛触发因素（神经肽降钙素基因相关肽）的剂量依赖性斜视反应，包括雌性小鼠在低于手动鬼脸量表检测到的剂量时的反应。最后，我们发现降钙素基因相关肽胰淀素会诱导雌性小鼠眯眼行为，但雄性小鼠则不会。这些数据表明，自动斜视测定可用作客观、实时、连续规模的疼痛测量，与手动鬼脸评估相比，可提供更高的精确度和实时分析。