真鲷视网膜结构及视觉特性研究──Ⅲ．真鲷视觉特性

STUDIES ON STRUCTURE OF THE RETINA AND VISUAL CHARACTERISTICS OF PAGROSOMUS MAJOR -Ⅲ. VISUAL CHARACTERISTICS OF PAGROSOMUS MAJOR

视网膜电图（ＥＲＧ）结果显示，真鲷Ｐａｇｒｏｓｏｍｕｓｍａｊｏｒ视网膜具混合型特征。强光明适应后，ｂ波阈值在８０ｍｉｎ回复至暗视水平。明适应过程中，ｂ波振幅存在Ｄ型和Ｒ型。其光谱敏感曲线在强背景光下（ｌｏｇＩＢ＝１．８）发生浦氏位移，峰值从４８４ｎｍ移至５２５ｎｍ，且从颜色光适应对Ｓλ曲线的影响等都表明，真鲷存在两种以上的光感受系统，且具辨色能力。浦氏位移的光强水平较高，说明辨色能力不会很强。

The waveforms of ERG reveal the features of mixed retina. After preexposure to high intensity light, the threshold for eliciting a contant b-wave return to the dark adapted level in a period of 80 mintltes. According to the level of light adaptation, the D-type and the R-type of the time course of change in b-wave sensitivity are observed in the retina. When the intensity of white background light is higher (logIB=-1. 8) the spectral sensitivity curve occurs Purkinje shift, the peak shifts from 484nm to 524nm.The change of the spectral sensitivity curve under chromatic light adaptation. All these show that the retina has more than two types of receptor system and has the ability of color discrimination, but is not strong.