L'osmorégulation et la régulation de l'eau dans les protoplastes de tubercules de radis (Raphanus sativus)

Abstract

In the present work it is found that protoplasts of the radish tuber with a disorganized cytoskeleton, thus dead, subjected to a hypotonic shock, obey the law of osmosis, while healthy ones absorb 6% more water. This means that some events related to metabolism are responsible for this difference. Furthermore, stimulating metabolism, by action on the Krebs cycle, results in absorption of water, while slowing it with an inhibitor of oxydative phosphorylation results in loss of water by the cells. It is concluded that a hydraulic control of turgor, modulated by the intensity of respiration, exists in these cells. This is probably due to a mechanism similar to that of osmoregulation. We call it hydroregulation.Key words: osmoregulation, water intake, water excretion, turgor, hydroregulation.