An evaluation of the mechanisms developmentally involved on cellular and extracellular glycosaminoglycans accumulation in chick embryo skin fibroblasts.
1. Ammonium chloride, a lysosomotropic amine known to inhibit lysosomal function, was administered to 7-day cultured and 14-day chick embryo skin fibroblasts to evaluate the relationship between synthesis, degradation and uptake of glycosaminoglycans (GAG). 2. Following amine treatment, the amount of 3H-glucosamine and 35SO4 labelled cellular GAG increased, was more at 14 days than at 7 days. Hyaluronic acid (HA) incorporation was mainly interested at 7 days and that of sulphated GAG at 14 days. 3. The extracellular accumulation declined proportionally to the cellular increase of undegraded GAG. HA was mainly affected at 7 days and sulphated GAG at 14 days. 4. The amine did not change 3H-HA uptake and it was unable to inhibit its degradation. 5. The products of degradation of uptaken 3H-HA were retained inside the cell. Those released by degradation of newly synthesized GAG flowed out of the cell.
Locci
P
P
Dipartimento di Medicina Sperimentale, Università di Perugia, Italy.
Evangelisti
R
R
Lilli
C
C
Stabellini
G
G
Becchetti
E
E
Carinci
P
P
D000818:Animals; D002451:Cell Compartmentation; D002454:Cell Differentiation; D002478:Cells, Cultured; D002642:Chick Embryo; D002852:Chromatography, Ion Exchange; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D006025:Glycosaminoglycans / Q000378:metabolism*; D006026:Glycoside Hydrolases / Q000378:metabolism; D006820:Hyaluronic Acid / Q000378:metabolism; D011506:Proteins / Q000032:analysis; D011509:Proteoglycans / Q000378:metabolism
D006025:Glycosaminoglycans; D011506:Proteins; D011509:Proteoglycans; D006820:Hyaluronic Acid; D006026:Glycoside Hydrolases