Local administration of TGF-β1 to reinforce the anterior abdominal wall in a rat model of incisional hernia.

The purpose of this study was to investigate different forms of the local application of TGF-β1 for augmentation of the anterior abdominal wall in an appropriate model of an incisional hernia. Sixty male Sprague Dawley rats were divided into six groups. Artificial defects of the anterior abdominal wall were closed with one of the following methods: running Prolene suture, Vicryl mesh, prolene suture followed by an intramuscular injection of 1 μg TGF-β1, Vicryl mesh coated with 1 μg TGF-β1, and prolene suture coated with 1 μg TGF-β1. A control group did not receive any defect and treatment. Six weeks after operation, tensile strength, collagen content, gene expression of collagen I and III, blood vessels, and thickness of collagen fibres were evaluated. Tensile strength was strongest in the controls (14.2 (10.5-18 N)). There was no increase in tensile strength due to the administration of TGF-β1. On the contrary, bolus injection of the growth factor resulted in a significantly decreased strength of the wound tissue when compared to the groups 1, 4, 5, and 6 (9.1 (4.2-9.1 N)). These results correlated with the gene expression of collagen I and III. Local application of TGF-β1 did not augment the strength of the abdominal wall after 6 weeks. [ABSTRACT FROM AUTHOR]