Wound contraction is a clinically important biological process because it frequently results in
contractures,
strictures, and
stenosis. If
collagen synthesis could be altered to minimize the
contracture, then the outcome could be improved.
Lathyrism produces poorly cross-linked
collagen in healing anastomosis, keeping a larger portion of the synthesized
collagen soluble. Ultimately, the amount of contracting
collagen is reduced, lowering the bulk and lessening the
contracture. The aim of this study was to observe the effects of a lathyrogen,
beta-aminopropionitrile (
BAPN), on the healing of colonic anastomosis. Thirty rats were divided into three groups.
Colostomy and anastomosis were performed on all rats. Intraperitoneal
saline solution (control) and either intraperitoneal (ip) or oral (po)
BAPN were administered. The rats were killed 1 week later. Anastomotic healing was assessed by bursting pressure and the
hydroxyproline content of the anastomotic tissues. Granulation tissue thickness, number of fibroblasts, inflammatory cells, and growing capillaries in granulation tissue per unit area were determined.
Collagen fibril diameters were estimated, and spatial arrangements of fibrils were examined by an electron microscope. All results were evaluated by Mann-Whitney U-test. The analyses of anastomotic tissues from
BAPN-treated rats showed a significantly reduced mean bursting pressure (158.9 +/- 12.3, 171.3 +/- 13.9, ip and po, respectively),
hydroxyproline content (8.9 +/- 2.6, 10.1 +/- 2.7), granulation tissue thickness (24.3 +/- 2.6, 16.1 +/- 5.2), number of inflammatory cells (37.8 +/- 4.3, 25 +/- 4.3), fibroblasts (3.2 +/- 1.1, 2.8 +/- 0.7), and a significantly reduced
collagen fiber diameter (15 +/- 2, 20 +/- 3) compared with those of control group (236.9 +/- 9, 14 +/- 4.4, 26.8 +/- 4.8, 39 +/- 2.6, 6.9 +/- 1.1, and 35 +/- 5, respectively). As a result,
collagen fibers were flimsy, and lost their regular parallel alignment in the
BAPN groups. On the other hand, a number of growing capillaries were found to be significantly increased in these groups (16.5 +/- 1.1, 18.2 +/- 0.7) compared to the control (6.7 +/- 1.3). Thus, it is suggested that
BAPN may be useful in the prevention of gastrointestinal
stricture formation.