明适应条件下鲤属鱼L-型外水平细胞反应的给光-瞬变成分

在明适应条件下鲤属鱼 L-型外水平细胞的反应显示明显的给光-瞬变成分(on-transient)、它与刺激波长有关——对蓝、绿光的反应比对红光的反应有更明显的瞬变成分,其光谱特性提示它与绿敏锥细胞的输入信号有关。与已报道的其它动物 L 型水平细胞的给光-瞬变成分不同,它的出现在一定范围内与网膜受照射的面积无关。绿色(502nm)和红色(706nm)闪光同时照射所引起反应的给光-瞬变成分比各自单独刺激时要显著得多,提示它也与绿敏锥细胞和红敏锥细胞输入的相互作用有关。

TRANSIENT ON-RESPONSES OF L-TYPE EXTERNAL HORIZONTAL CELLS IN THE LIGHT-ADAPTED CYPRINID RETINA

Responses of L-type external horizontal cells(LHCs)of the cyprinid retinadeveloped an initial on-transient during the course of light adaptation.Theon-transient is wavelength-dependent,being much more prominent to blue andgreen lights than to red light.From its spectral properties,the on-transient wasthought to be related with input from green-sensitive cones.Unlike the on-transientreported in other species,such as turtle and pikeperch,the on-transitnt of cyprinidaecould not be eliminated by decreasing the retinal area illuminated.Furthermore,compared to responses to either 502 nm or 706 nm flash alone,response to a mixedflash of both wavelengths exhibited a more prominent on-transient,suggesting thatinteraction between inputs from red-sensitive and green-sensitive cones may bepartly responsible for the generation of the on-transient.