Bilotta J, Saszik S, Sutherland S E
Department of Psychology and Biotechnology Center, Western Kentucky University, Bowling Green 42101, USA.
Dev Dyn. 2001 Dec;222(4):564-70. doi: 10.1002/dvdy.1188.
Anatomical studies of the developing zebrafish retina have shown that rods approach maturity at about 15 days postfertilization (dpf). Past work has examined the photopic spectral sensitivity function of the developing zebrafish, but not spectral sensitivity under dark-adapted conditions. This study examined rod contributions to the dark-adapted spectral sensitivity function of the ERG b-wave component in developing zebrafish. ERG responses to stimuli of various wavelengths and irradiances were obtained from dark-adapted fish at 6-8, 13-15, 21-24, and 27-29 dpf. The results show that dark-adapted spectral sensitivity varied with age. Spectral sensitivity functions of the 6-8 and 13-15 dpf groups appeared to be cone dominated and contained little or no rod contributions. Spectral sensitivity functions of the 21-24 and 27-29 dpf groups appeared to have both rod and cone contributions. Even at the oldest age group tested, the dark-adapted spectral sensitivity function did not match the adult function. Thus, consistent with anatomical findings, the rod contributions to the ERG spectral sensitivity function appear to develop with age; however, these contributions are still not adult-like by 29 dpf, which is contrary to anatomical work. These results illustrate that the zebrafish is an excellent model for visual development.
对发育中的斑马鱼视网膜进行的解剖学研究表明，视杆细胞在受精后约15天（dpf）接近成熟。过去的研究探讨了发育中的斑马鱼的明视觉光谱敏感度函数，但未研究暗适应条件下的光谱敏感度。本研究检测了视杆细胞对发育中斑马鱼视网膜电图（ERG）b波成分暗适应光谱敏感度函数的贡献。在6 - 8、13 - 15、21 - 24和27 - 29 dpf时，从暗适应的斑马鱼获得了对各种波长和辐照度刺激的ERG反应。结果表明，暗适应光谱敏感度随年龄变化。6 - 8 dpf组和13 - 15 dpf组的光谱敏感度函数似乎以视锥细胞为主，视杆细胞贡献很少或没有贡献。21 - 24 dpf组和27 - 29 dpf组的光谱敏感度函数似乎同时有视杆细胞和视锥细胞的贡献。即使在测试的最老年龄组中，暗适应光谱敏感度函数也与成年鱼的函数不匹配。因此，与解剖学发现一致，视杆细胞对ERG光谱敏感度函数的贡献似乎随年龄发展；然而，到29 dpf时这些贡献仍未达到成年水平，这与解剖学研究结果相反。这些结果表明斑马鱼是视觉发育的优秀模型。
