Dependence of Collagen Synthesis by Embryonic Chick Tendon Cells on the Extracellular Concentrations of Glutamine

An agent in rheumatoid synovial fluid which stimulates collagen synthesis by embryonic chick tendon cells was identified as glutamine. The stimulating effect was observed only at a subnormal concentration of proline (0.02 mM). The concentration of glutamine in rheumatoid synovial fluid is about 2.5 mM but it falls rapidly during storage even at -20 degrees C. Collagen synthesis is shown to depend on the extracellular concentrations of glutamine and proline in addition to any connective tissue activating factors.