Semple-Rowland S L, Dawson W W
Lab Anim Sci. 1987 Jun;37(3):289-98.
This study determined the minimum cyclic [12L:12D] light intensity which produces retinal damage in albino (Sprague-Dawley) rats raised from birth to 15 weeks of age under a cyclic light intensity of 6 lux. Four experimental light intensities were tested, including: 1345, 270, 130 and 65 lux. Control animals remained under 6 lux. For each of the intensities tested, the retinas of groups of six rats were evaluated after various durations of light exposure for physiological and morphological evidence of light damage. The indices of damage were (a) histological and morphometric changes in the retina and (b) changes in the amplitude of the b-wave of the electroretinogram. The data indicated that light intensities of 1345 or 270 lux severely damaged retinas of albino rats within 3-7 days of the initiation of light exposure. Exposure to 130 or 65 lux produced much less dramatic changes in the responsiveness and morphology of the retina which did not appear to be permanent. Based on these results, a reasonable estimate for the threshold cyclic light intensity which produces damage to retinas of albino rats raised under 6 lux lies between 130 and 270 lux, or approximately 1.3 log units above the light intensity under which the animals were raised.
本研究确定了在6勒克斯的周期性光照强度下，从出生饲养至15周龄的白化（斯普拉格-道利）大鼠产生视网膜损伤的最小周期性[12小时光照：12小时黑暗]光照强度。测试了四种实验光照强度，包括：1345、270、130和65勒克斯。对照动物饲养在6勒克斯光照条件下。对于每个测试强度，在不同光照暴露时长后，对每组六只大鼠的视网膜进行评估，以寻找光损伤的生理和形态学证据。损伤指标为：（a）视网膜的组织学和形态测量学变化，以及（b）视网膜电图b波振幅的变化。数据表明，1345或270勒克斯的光照强度在光照开始后的3 - 7天内严重损伤了白化大鼠的视网膜。暴露于130或65勒克斯下，视网膜的反应性和形态学变化则小得多，且似乎并非永久性的。基于这些结果，对于在6勒克斯光照下饲养的白化大鼠，产生视网膜损伤的阈值周期性光照强度的合理估计值介于130和270勒克斯之间，或比动物饲养时的光照强度高约1.3个对数单位。
