Home >> Papers-from-the-department-of-marine-bio-volume-11 >> Properties Of Photogenin And to With Special Reference To_2 >> Response of Injured Cells

Response of Injured Cells

respond, noctilucas and stimulation

RESPONSE OF INJURED CELLS.

If a number of noctilucas are punctured with a needle, causing the cells to collapse, and are then subjected to an interrupted current, they respond just as uninjured cells do. Such punctured and collapsed cells likewise give a normal response when stimulated mechanically—i. e., by pressure of a cover-slip.

Noctilucas are injured by a few shocks of the strong induced current; the protoplasm shrinks away from the cell-wall, leaving a clear area at the periphery. If the animal is further subjected to an induced cur rent, there is again a response, the protoplasmic area becoming lumi nous, while the clear peripheral area does not. After a short time the cell collapses and the animal appears as a shrunken mass of protoplasm within an irregular membrane. These shrunken animals also respond at the break of a weak induced current with a flash, just as normal cells do; and they likewise give a normal response to mechanical stim ulation—i. e., if pressed by a needle. It is thus shown that injury to a

noctiluca does not interfere with its response to mechanical or elec trical stimulation.

If, however, the injury to the cells is too great, and the cells are completely broken to pieces, they do not respond to stimulation. By pressing a mass of noctilucas through cheese-cloth, a filtrate was ob tained containing many empty membranes and fragments of cells, visible under the microscope. This filtrate, although luminous, did not respond to electrical stimulation. Another filtrate obtained by pressing a mass of noctilucas through fine-meshed bolting-cloth, and tested while still luminous, did not respond to electrical stimulation. It is possible, however, that the fact that the noctiluca juice is acid may have some effect on the response in these cases.