title: Peritoneal adhesion formation and reformation tracked by sequential laparoscopy: optimizing the time point for adhesiolysis.
abstract: BACKGROUND
  In a high proportion of patients, operatively lysed adhesions reform. Using a rabbit adhesiogenesis model, this study assessed the efficacy of adhesiolysis and examined how this relates to the tissue composition of adhesions at the time of lysis.
  
  
  METHODS
  Polypropylene meshes (5 x 3.5 cm) were implanted on the parietal peritoneum of New Zealand white rabbits. Some animals were killed 3, 7, 14, and 90 days postimplantation to obtain adhesion tissue. Adhesion formation/reformation was monitored by sequential laparoscopy in other animals kept for 90 days and in a separate experimental group subjected to adhesiolysis at 3 days postimplantation. Immune and inflammatory response markers were determined by immunohistochemical, Western blotting, and real-time reverse transcriptase polymerase chain reaction procedures in adhesion tissue; areas occupied by adhesions were quantified in meshes.
  
  
  RESULTS
  In animals undergoing adhesiolysis, mesh areas covered by adhesions were significantly decreased at each follow-up time and affected areas became mesothelialized. Increased transforming growth factor (TGF)-beta1 expression was detected in adhesions at 3 days. Greatest TGF-beta1 and vascular endothelial growth factor (VEGF) protein expressions were observed at 7 days, whereas genetic overexpression was noted at 14 days. Active inflammatory cells peaked at the 7-day time point.
  
  
  CONCLUSIONS
  Adhesions formed at 3 days; at this critical time, an adhesiolysis was effective in preventing reformation of future adhesions. TGF-beta1 gene and protein expression were increased in 3-day adhesions with respect to the omentum. Levels of active TGF-beta1 and VEGF were increased at 7 days, along with the inflammatory response at this time point related to tissue remodeling, which led to stabilization of adhesions.
authors.affiliation: Department of Medical Specialities, Faculty of Medicine, Networking Research Center on Bioengineering, Biomaterials and Nanomedicine, University of Alcalá, Alcalá de Henares, Madrid, Spain.
authors.forename: Verónica
authors.initials: V
authors.lastname: Gómez-Gil
authors.forename: Natalio
authors.initials: N
authors.lastname: García-Honduvilla
authors.forename: Gemma
authors.initials: G
authors.lastname: Pascual
authors.forename: Marta
authors.initials: M
authors.lastname: Rodríguez
authors.forename: Julia
authors.initials: J
authors.lastname: Buján
authors.forename: Juan M
authors.initials: JM
authors.lastname: Bellón
mesh_terms: D000818:Animals; D010535:Laparoscopy; D008297:Male; D009852:Omentum; D010532:Peritoneal Diseases / Q000209:etiology / Q000473:pathology* / Q000601:surgery*; D011817:Rabbits; D012008:Recurrence; D013526:Surgical Mesh; D013997:Time Factors; D000267:Tissue Adhesions / Q000209:etiology / Q000473:pathology / Q000601:surgery; D053773:Transforming Growth Factor beta1 / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000378:metabolism
chemical_list: D053773:Transforming Growth Factor beta1; D042461:Vascular Endothelial Growth Factor A