正常SD大鼠视网膜电图敏感度功能的发育

目的纵向研究正常SD大鼠视网膜电图（ERG）敏感度功能的发育。方法实验研究。SD大鼠22只（22眼），分别在出生后16 d、18 d、（30±2）d和（64±2）d记录暗适应ERG。暗适应后用逐渐递增的白光刺激记录一系列的ERG。通过曲线拟合获得饱和a波波幅（Rmp3）和敏感度（S）。通过曲线回归获得最大b波波幅（Vmax）和敏感度（σ）。采用方差分析检验ERG参数在各时间点之间的差异。结果随着生长发育S和logσ逐渐增高。Rmp3在出生后18 d时最高，以后随着生长发育逐渐下降。Vmax在出生后（30±2）d时最高，以后随着生长发育逐渐下降。结论ERG的敏感度随着生长发育而增高，反映了SD大鼠视杆细胞功能的发育特点。

Functional development changes in electroretinographic sensitivity in the normal SD rats

ObjectiveTo evaluate the longitudinal development of electroretinographic （ERG） sensitivity in normal SD rats. MethodsIn an experimental study， scotopic ERGs of 22 eyes of 22 rats were recorded postnatally （P） on P16， P18， P30±2 and P64±2 days. The stimulus light was white with gradient intensities. Rod sensitivity （S） and the saturated a wave （Rmp3） were obtained by fitting Hood′s function. Sensitivity of the b wave （σ） and maximum b wave （Vmax） were calculated by regression using the Naka-Rushton function. ANOVA was used to test the differences in ERG parameters at different postnatal ages. ResultsBoth rod sensitivity （S） and b wave sensitivity （σ） increased with development. The highest Rmp3 was obtained at P18 while Vmax occurred at P30±2 days. ConclusionAlteration of rod sensitivity increased with postnatal development and reflected the developmental characteristics of rod function of SD rat.