Melanopsin in ocular tissue after corneal abrasion

Melanopsin is a non-image forming photoreactive protein that has diverse roles in multiple tissues. This study examines how melanopsin expression changes after corneal abrasion. Corneal abrasion is the most common form of eye injury and can cause severe pain and photoallodynia. Behavior of rats was measured using orbital tightening, a part of the grimace scale. Then melanopsin positive cells in the retina were counted and volume of melanopsin in the iris was calculated at baseline, 24h and 1wk. Finaly the prominence of the pupillary ruff into the pupil was measured. These data indicate that pain behaviors, melanopsin in the iris and prominence of the pupillary ruff all peak at 24h after corneal abrasion.黑视蛋白（Melanopsin）是一类非成像型光反应蛋白，在多种组织中具有多样生物学功能。本研究旨在探讨角膜擦伤后黑视蛋白的表达变化规律。角膜擦伤是临床最常见的眼部损伤类型，可引发剧烈疼痛及光诱发性痛觉超敏（photoallodynia）。本研究采用大鼠痛苦表情评分量表中的眼眶收紧评分法对大鼠行为学表现进行量化测定，随后分别在基线、擦伤后24小时及1周三个时间点，对视网膜内的黑视蛋白阳性细胞进行计数，并计算虹膜内黑视蛋白的相对体积，最后还测量了瞳孔缘向瞳孔腔内的突出程度。上述实验数据表明，角膜擦伤后，大鼠的痛觉行为、虹膜内黑视蛋白水平以及瞳孔缘突出程度均在擦伤后24小时达到峰值。