The effects of lathyrogens on intestinal anastomoses in the rat

Submucosal collagen provides strength to the intestinal wall. In order to assess the importance of collagen fibers for the developing strength of intestinal anastomoses we have sought to prevent postoperative collagen crosslinking by administration of lathyrogens. Rats, receiving both an ileal and a colonic anastomosis, were treated with either D-penicillamine or beta-aminopropionitrile from 1 day before operation. Animals were sacrificed 7 days postoperatively and bursting pressures, bursting sites, and anastomotic collagen (hydroxyproline) content and solubility were determined. D-Penicillamine, in a dose of 500 mg/kg/day and administered orally, had no effect at all. beta-Aminopropionitrile, in a dose of 625 mg/kg/day and given orally or intraperitoneally, significantly increased the acid solubility of anastomotic hydroxyproline in both ileum and colon without affecting total hydroxyproline content or concentration. Bursting pressures of the anastomotic segments were lowered, more significantly in colon than in ileum. Also, the bursting site was found more frequently in the anastomotic area in these animals. By inhibiting the formation of crosslinks in intestinal wounds with beta-aminopropionitrile, the anastomotic strength was reduced. These results demonstrate the importance of collagen in maintaining anastomotic integrity and at the same time emphasize that not only the quantity but also, and perhaps even more so, the quality of the collagen should be taken as an index of healing.