RESUMO
Alkaline phosphatases from mammalian bone are inhibited much more than chick bone alkaline phsophatase by levamisole and compound R8231. Doses of R8231 (10(-4) to 10(-5) M) that almost completely inhibit mammalian alkaline phosphatases do not inhibit the growth of embryonic rat femurs in vitro. R8231 should be an excellent biological probe for the function of alkaline phosphatase in bone metabolism.
Assuntos
Fosfatase Alcalina/antagonistas & inibidores , Osso e Ossos/enzimologia , Levamisol/farmacologia , Tetramizol/análogos & derivados , Animais , Galinhas , Embrião de Mamíferos , Embrião não Mamífero , Cinética , Camundongos , Coelhos , Especificidade da Espécie , Relação Estrutura-Atividade , Tetramizol/farmacologiaRESUMO
1. Pig synovial fibroblasts in culture were studied to determine if they were an easily reproducible model system for studying the actions of cytokines and growth factors on human synovial cells. The biochemical analyses were conducted by activity assays, enzymography and Northern blot. 2. Human recombinant interleukin-1 alpha, basic fibroblast growth factor and transforming growth factor-beta 1 were studied in combinations because of their known involvement in controlling tissue remodelling. 3. The response of pig fibroblasts to these agents, in terms of the expression of matrix metalloproteinases (collagenase, gelatinase and stromelysin) and their inhibitors (TIMPs), show that they behave similarly enough to human cells for use when supplies of human primary cells are unavailable.