STIMULATION BY RECOMBINANT HUMAN GROWTH-HORMONE OF GROWTH AND DEVELOPMENT OF REMAINING BOWEL AFTER SUBTOTAL ILEOJEJUNECTOMY IN RATS

The impact of human recombinant growth hormone (GH) after massive small bowel resection was studied in 38 weaning female Wistar rats (65 +/- 5 days old; 193 +/- 26 g). Animals underwent a 80% small bowel resection, leaving in place similar lengths of jejunum and ileum. Animals were assigned to four groups: group A (n = 9), small bowel resection only; group B (n = 10), resection and treatment with 0.2 GH units (GHU) s.c. every other day; group C (n = 9), resection and 0.4 GHU; and group D (n = 10), laparotomy without intestinal resection. Twenty-eight days later, weight gain (percentage of initial weight) was 1 +/- 3 in group A, 12 +/- 8 in group B, 12 +/- 9 in group C, and 16 +/- 7 in group D; p < 0.001, groups B-D. Time to recover initial weight was 26.2 +/- 3.3 days in group A; 11.7 +/- 5.4 days in group B (p < 0.001); and 16 +/- 6.1 days in group C (p < 0.001 vs. A). The size of the intestinal remnant after the rats were killed was 1.3 +/- 0.6 cm (13 +/- 10% of initial length) in A; 5.15 +/- 2.4 cm (37 +/- 18%) in B (p < 0.01); 4.2 +/- 2.3 cm (33 +/- 20%) in C (p < 0.01 vs. A); and 4.4 +/- 3.5 cm (5.8 +/- 4.9%) in D (p < 0.001 vs A). Villus height and diameter, average number of mitosis per field, and muscular layer and wall thickness were greater in groups A, B, and C than in group D (p < 0.001). Villus height and muscular thickness of the jejunal part were increased in group C compared with A (p < 0.05). In conclusion, GH improves the postoperative intestinal adaptation process in terms of both weight gain and small bowel lengthening.