Objective: To compare expression of matrix metalloproteinase (MMP-1) and tissue inhibitor of MMP (TIMP-1) in serosal tissue of intraperitoneal organs and adhesions.
Design: Prospective and cross-sectional study.
Setting: Academic research centers.
Patient(s): Patients undergoing abdominal or pelvic surgery.
Intervention(s): MMP-1 and TIMP-1 expression.
Main outcome measure(s): Expression of messenger ribonucleic acid (mRNA) and protein was measured by using quantitative reverse transcription polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay.
Result(s): Serosal tissue of intraperitoneal organs and adhesions express MMP-1 and TIMP-1 mRNA and protein at levels that are consistently varied with 10- to 10,000-fold and 2- to 10-fold higher TIMP, mRNA and protein, respectively. Parietal peritoneum, fallopian tubes and ovaries express higher MMP-1 mRNA levels compared with uterus and adhesions; the lowest expression is found in small and large bowels, subcutaneous tissue. and omentum. Expression of TIMP-1 mRNA was less variable; the highest level was found in the uterus and the lowest in subcutaneous tissue and small bowels. There was less variability in MMP-1 and TIMP-1 protein content than mRNA expression; ovaries and adhesions contained the highest MMP-1 and TIMP-1 levels, respectively, and peritoneum contained the lowest. The MMP-1 and TIMP-1 content and ratios further indicate limited MMP-1 proteolytic activity. Although tissues from premenopausal women express more MMP-1 and TIMP-1, expression did not differ by sex or age.
Conclusion(s): Because MMP-1 and TIMP-1 expression varies consistently among the serosal tissues of peritoneal organs and adhesions, and because tissue injury alters their expression, site-specific variations in expression of these substances may predispose a particular organ to develop more adhesions.