Regulation of collagenase inhibitor production in chondrosarcoma chondrocytes

Conference · Fri May 01 00:00:00 EDT 1987 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6074839

Harper, J; Harper, E

Swarm rat chondrosarcoma chondrocytes produce an inhibitor of collagenase. This inhibitor is similar to those isolated from normal cartilage tissues. These cells will synthesize proteins in the absence of serum. Since serum contains inhibitors of collagenase, it is necessary to culture cells without serum in order to obtain accurate measurements of enzyme and inhibitor levels. They examined the effect of insulin on inhibitor secretion by cultures of Swarm rat chondrosarcoma chondrocytes. They observed a 2.5 to 3.5 fold stimulation of inhibitory activity in the presence of as little as 10 ng/ml insulin as compared to controls in serum free Dulbecco's modified Eagle's medium supplemented with 4.5 g/l glucose. The units of inhibitor were determined over a 7 day culture period. Medium was harvested daily and assayed for collagenase activity and for inhibition of a known collagenase from rabbit skin or human skin, using the /sup 14/C-glycine peptide release assay. The amount of inhibitor obtained from days 2 through 7 were: 1.4 unit (control), 3.8 units (10 ng/ml insulin), 5.2 units (1 ..mu..g/ml insulin). The addition of 1 mM dibutyryl cyclic AMP to these chondrocytes in the presence of 1 ..mu..g/ml insulin caused a decrease in the level of inhibitor, suggesting that a dephosphorylation event may be necessary for this stimulation by insulin to occur.

• Research Organization: Univ. of California, San Diego, La Jolla
• OSTI ID: 6074839
• Report Number(s): CONF-870644-
• Journal Information: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States), Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Vol. 46:6; ISSN FEPRA
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
AMP
ANIMALS
BIOCHEMICAL REACTION KINETICS
CARBOXYLIC ACIDS
ENZYME ACTIVITY
ENZYME INHIBITORS
ENZYMES
GLYCINE
HORMONES
HYDROLASES
INSULIN
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
MAMMALS
NUCLEOTIDES
ORGANIC ACIDS
ORGANIC COMPOUNDS
PEPTIDE HORMONES
PEPTIDE HYDROLASES
RATS
REACTION KINETICS
RESPONSE MODIFYING FACTORS
RODENTS
SECRETION
TRACER TECHNIQUES
TRITIUM COMPOUNDS
VERTEBRATES