The effect of light on cells in fluorescent solution after addition of potassium cyanide

Since potassium cyanide inhibits certain oxidative processes in living matter such as respiration in plants and animals, the segmentation of fertilized egg cells, etc., behaving in this regard like an atmosphere of hydrogen, it might be expected that the destructive action of light upon cells suspended in fluorescent solutions, an action that is in part at least one of oxidation, would be diminished or obliterated by the addition of potassium cyanide to such solutions. On the contrary, the addition of very small quantities of potassium cyanide to sea water containing fluorescent substances (eosin, methylene blue, neutral red and combinations of these) causes a marked acceleration of the destructive action of visible light rays upon star-fish eggs immersed in these solutions. The chemical character of the fluorescent substances being different, it is evident that the chemical character of the fluorescent substance does not influence the action of potassium cyanide. But if starfish eggs in such solutions be deprived of oxygen, by substituting for air an atmosphere of hydrogen, they no longer undergo deterioration under the action of light and this result remains uninfluenced by the addition of potassium cyanide to the solution. It asserts this accelerating action only if added to eggs in fluorescent solutions exposed to light. If the cells were first immersed in a solution of potassium cyanide in the dark and afterwards transferred to the fluorescent solution in the light, potassium cyanide did not show any effect. Also control experiments in which small amounts of acid, alkali or certain alkaloids took the place of potassium cyanide showed no such results.

It would seem therefore that the oxidative processes, which perhaps in combination with other chemical processes, take place through the action of light upon cells in fluorescent solution, must be of a different character from the oxidative processes taking place in respiration arid in cell division, since the former are accelerated instead of, like the latter, being inhibited by the action of potassium cyanide.