Journal of Cell Science, Vol 4, 89-103, Copyright © 1969 by Company of Biologists

Submitted on March 6, 1968

Endocytosis of Sugars in Embryonic Skeletal Tissues in Organ Culture

I. General Introduction and Histological Effects

¹ Strangeways Research Laboratory, Wort's Causeway, Cambridge, England

The addition of sucrose to a chemically defined culture medium caused intense cytoplasmic vacuolation of the perichondrial, oesteogenic arid articular cartilage cells of limb-bone rudiments from 8-day embryonic chicks grown in organ culture. The rest of the cartilage appeared unaffected by the sugar. The osteocytes were intensely vacuolated; the bone matrix was much less dense than that of the controls and had an abnormal fibrillar structure. When the explants were transferred to medium without sucrose, after 6 days vacuolation had almost disappeared.

The effect of the sucrose was dose-dependent; at a concentration of 0.32M the sugar was highly toxic; at 0.16M the explants survived and vacuolation of the chondrocytes extended further into the cartilage than at 0.08M. A similar vacuolation of the cells in response to sucrose was seen in the isolated shafts of the limb-bones and in the mandibular rami from 11- to 13-day embryos; in the sucrose-treated explants osteogenesis was arrested and in places the bone showed osteolytic changes.

In the absence of glucose, 8-day limb-bone rudiments failed to grow and rapidly degenerated in medium containing 0.08 M sucrose, indicating that sucrose was very little if at all metabolized.

Explants of 8-day rudiments grown for 8 days in the presence of 0.8M glucose showed no vacuolation; dextran had some effect, and both mannitol and sorbitol caused vacuolation.

Note:

Member of Medical Research Council's External Staff.