%0 Journal Article
%T Cobalt ions enhance light responsiveness of carp cone horizontal cells in low calcium
%A WANG Hailong
%A YANG Xiongli
%A <br>王海龙
%A 杨雄里
%J 中国科学C辑(英文版)
%D 1996
%I Springer
%X Effects of cobalt ions (Co 2+ ) on horizontal cells in low extracellular calcium were examined in isolated, superfused carp retinas. While 0.1mmol/L Co 2+  completely suppressed both rod- and cone-driven horizontal cells in normal Ringer's solution, it enhanced light responses of cone horizontal cells in low (0.1mmol/L) calcium. The enhancement of the cone horizontal cell response by Co 2+ was not caused by changes in light responsiveness of cone photoreceptors. Moreover, application of 50μmol/L IBMX, an inhibitor of phosphodiester enzyme, reduced the suppressive effect of 0.1 mmol/L Co 2+  in normal Ringer's solution. In consequence, the above-described enhancement of the cone horizontal cell light responsiveness may be due to a depolarization of cones caused by low calcium, which increases the activity of voltage-dependent calcium channels at cone terminals.
%K light responsiveness
%K horizontal cell
%K low calcium
%K cobalt<br>
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=90BA3D13E7F3BC869AC96FB3DA594E3FE34FBF7B8BC0E591&jid=180CF3A72E750F3261A8A60EDC957784&aid=2E513A6B862C4B5F4455E7334E88AA00&yid=8A15F8B0AA0E5323&vid=7C3A4C1EE6A45749&iid=38B194292C032A66&sid=B799C1769FCACDC8&eid=4FE459D71E3BF8EB&journal_id=1674-7305&journal_name=ScienceChina.Lifesciences&referenced_num=0&reference_num=0