Growth hormone reduces bacterial translocation in radiation enteritis in the rat.

BACKGROUND: Radiotherapy may be considered as one of the most effective treatments for digestive tumours. This procedure has major side effects, especially in fast growing tissues like intestinal mucosa. The administration of drugs that reduce or avoid radiation injury of the intestinal mucosa may be clinically advantageous. Growth hormone is a peptide suitable for this purpose by modifying cell proliferation within the intestinal crypt. MATERIAL AND METHOD: Adult male Wistar rats were used in a model of abdominal irradiation. Each irradiated animal received 1200 cGy under anaesthesia and was sacrificed four and seven days later. The animals were treated with either saline or growth hormone (1 mg/kg/day) beginning immediately after the irradiation treatment. On the day of sacrifice, intestinal samples were taken for morphometric measurements and mesenteric lymph nodes for bacterial translocation. RESULTS: Mortality was of 50% approximately and was not affected by growth hormone treatment in irradiated animals. Bacterial translocation increased (p < 0.05) in irradiated animals whereas no significant increase was observed in rats treated with growth hormone. Growth hormone promotes an earlier growth of intestinal villi in irradiated animals (p < 0.05). CONCLUSIONS: Growth hormone promotes the morphologic adaptation of intestinal mucosa after abdominal irradiation, reducing bacterial translocation in rat.