Affiliation:
1. Universidade Federal do Paraná, Brasil
Abstract
The Antarctic fish Trematomus newnesi (Boulenger, 1902) occurs from benthic to pelagic habitats, in seasonally and daily varied photic conditions that induce retinomotor movements. Fish were experimentally kept under constant darkness or light, and 12Light/12Dark for seven days. The retinomotor movement of the pigment epithelium was established through the pigment index, while that of the cones was calculated as the length of the myoid. The retinomotor movement of the pigment epithelium in T.newnesi,revealed that the adaptation to constant light occurred in the one hour of exposure, remaining constant for the next seven days. However, the adaptation to constant darkness, was slower. The difference between the mean values of the pigment indices in the time intervals of sampling was significant in the first hours of the experiment, and only after six hours they were not significant any more. The myoid of cones became elongated in darkness and contracted in light. In the experiments where T.newnesiwas exposed initially to 12 hours light followed by 12 hours darkness 12 was evidenced that the speed and intensity of the retinomotor movements was higher when darkness changed into light, than when light changed into darkness.
Subject
Animal Science and Zoology
Reference29 articles.
1. Les responses retinomotrices: caracteres et mechanismes;ALI M.A.;Vision Research,1971
2. Vision in fishes;ALI M.A.,1975
3. Antarctic ecology;ANDRIASHEV A.P.,1970
4. Myosin-I in retinal pigment epithelial cells;BRECKLER J.;Investigative Ophthalmology and Visual Science,1994
5. Light and circadian regulation of retinomotor movement;BURNSIDE B.;Progress in Brain Research,2001
Cited by
7 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献