Tzameret Adi, Sher Ifat, Edelstain Victoria, Belkin Michael, Kalter-Leibovici Ofra, Solomon Arieh S, Rotenstreich Ygal
Goldschleger Eye Research Institute, Sheba Medical Center, Tel HaShomer, Israel.
Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
Vis Neurosci. 2019 Jan;36:E002. doi: 10.1017/S095252381800007X.
Preserving of vision is the main goal in vision research. The presented research evaluates the preservation of visual function in Royal College of Surgeon (RCS) rats using a depth perception test. Rats were placed on a stage with one side containing an illusory steep drop ("cliff") and another side with a minimal drop ("table"). Latency of stage dismounting and the percentage of rats that set their first foot on the "cliff" side were determined. Nondystrophic Long-Evans (LE) rats were tested as control. Electroretinogram and histology analysis were used to determine retinal function and structure. Four-week-old RCS rats presented a significantly shorter mean latency to dismount the stage compared with 6-week-old rats (mean ± standard error, 13.7 ± 1.68 vs. 20.85 ± 6.5 s, P = 0.018). Longer latencies were recorded as rats aged, reaching 45.72 s in 15-week-old rats (P < 0.00001 compared with 4-week-old rats). All rats at the age of 4 weeks placed their first foot on the table side. By contrast, at the age of 8 weeks, 28.6% rats dismounted on the cliff side and at the age of 10 and 15 weeks, rats randomly dismounted the stage to either table or cliff side. LE rats dismounted the stage faster than 4-week-old RCS rats, but the difference was not statistically significant (7 ± 1.58 s, P = 0.057) and all LE rats dismounted on the table side. The latency to dismount the stage in RCS rats correlated with maximal electroretinogram b-wave under dark and light adaptation (Spearman's rho test = -0.603 and -0.534, respectively, all P < 0.0001), outer nuclear layer thickness (Spearman's rho test = -0.764, P = 0.002), and number of S- and M-cones (Spearman's rho test = -0.763 [P = 0.002], and -0.733 [P = 0.004], respectively). The cliff avoidance test is an objective, quick, and readily available method for the determination of RCS rats' visual function.
保护视力是视觉研究的主要目标。本研究通过深度感知测试评估皇家外科学院（RCS）大鼠的视觉功能保护情况。将大鼠放置在一个平台上，平台一侧有一个虚幻的陡坡（“悬崖”），另一侧有一个极小的落差（“平台”）。测定大鼠从平台上下来的潜伏期以及第一只脚踏上“悬崖”一侧的大鼠百分比。非营养不良的长 Evans（LE）大鼠作为对照进行测试。使用视网膜电图和组织学分析来确定视网膜功能和结构。4 周龄的 RCS 大鼠从平台上下来的平均潜伏期明显短于 6 周龄的大鼠（平均值±标准误，13.7±1.68 秒对 20.85±6.5 秒，P = 0.018）。随着大鼠年龄增长，潜伏期延长，15 周龄大鼠的潜伏期达到 45.72 秒（与 4 周龄大鼠相比，P < 0.00001）。所有 4 周龄的大鼠第一只脚都踏在平台一侧。相比之下，8 周龄时，28.6%的大鼠从悬崖一侧下来，10 周龄和 15 周龄时，大鼠随机从平台上下来到平台或悬崖一侧。LE 大鼠从平台上下来的速度比 4 周龄的 RCS 大鼠快，但差异无统计学意义（7±1.58 秒，P = 0.057），所有 LE 大鼠都从平台一侧下来。RCS 大鼠从平台上下来的潜伏期与暗适应和明适应下的最大视网膜电图 b 波相关（斯皮尔曼等级相关系数检验分别为 -0.603 和 -0.534，所有 P < 0.0001），与外核层厚度相关（斯皮尔曼等级相关系数检验 = -0.764，P = 0.002），与 S 视锥细胞和 M 视锥细胞数量相关（斯皮尔曼等级相关系数检验分别为 -0.763 [P = 0.002]和 -0.733 [P = 0.004]）。悬崖回避测试是一种客观、快速且易于使用的方法，可用于测定 RCS 大鼠的视觉功能。
