INHIBITORY EFFECT OF CEPHALOTHIN ON MATRIX METALLOPROTEINASE ACTIVITYAROUND LOOSE HIP PROSTHESES

The inhibitory effects of drugs on matrix metalloproteinase (MMP) acti vity in tissues around sites of loose total hip arthroplasty (THA) pro stheses were studied. For activity measurements, a DNP-S (dinitropheny l-Pro-Gln-Gly-Ile-Ala-Gly-D-ARg) peptide degradation assay was perform ed by means of high-performance liquid chromatography. Neutral salt ti ssue extracts revealed significantly elevated MMP activity in THA samp les compared with that in noninflammed synovial tissue from the knee j oint, This elevation was markedly inhibited by cephalothin, but not by doxycycline, tetracycline, or gentamicin. These results indicate that cephalothin can inhibit MMP activity in reactive periprosthetic tissu e and thus reduce, by a nonantimicrobial mechanism, the tissue destruc tion associated with the loosening of THA implants.