Effect of oxygen tension and lactate concentration on keratan sulphate and chondroitin sulphate biosynthesis in bovine cornea.
Calf cornea slices were incubated with [U-14C]glucose, in varying pO2 or lactate concentrations. Acid glycosaminoglycans were separated by ion-exchange chromatography after papain digestion. The percentage radioactivity incorporated into keratan sulphate increased markedly with decreased oxygen tension, whereas a concomitant relative decrease of the biosynthesis of glycosaminoglycuronans occurred. Similar results were obtained with increased lactate concentration. Our findings support the idea that keratan sulphate is a functional substitute for chondroitin sulphate in conditions of oxygen lack (Scott, J.E. and Haigh, M. (1988) J. Anat. 158, 95-108).
Balduini
C
C
Department of Biochemistry, University of Pavia, Italy.
De Luca
G
G
Passi
A
A
Rindi
S
S
Salvini
R
R
Scott
J E
JE
D000818:Animals; D002250:Carbon Radioisotopes; D002417:Cattle; D002809:Chondroitin Sulfates / Q000096:biosynthesis*; D002852:Chromatography, Ion Exchange; D003315:Cornea / Q000187:drug effects / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis / Q000302:isolation & purification; D007632:Keratan Sulfate / Q000096:biosynthesis*; D007773:Lactates / Q000494:pharmacology*; D019344:Lactic Acid; D010100:Oxygen / Q000494:pharmacology*; D010206:Papain / Q000378:metabolism
D002250:Carbon Radioisotopes; D006025:Glycosaminoglycans; D007773:Lactates; C018303:glycosaminoglucuronates; D019344:Lactic Acid; D002809:Chondroitin Sulfates; D007632:Keratan Sulfate; D010206:Papain; D005947:Glucose; D010100:Oxygen