EFFECTS OF SHORT-TERM GROWTH-HORMONE THERAPY IN RATS UNDERGOING 75-PERCENT SMALL INTESTINAL RESECTION

Thirty 250-g male rats underwent 75% small intestinal resection and received s.c. injections of water [short gut (SG)-control], human growth hormone (hGH) at 0.1 mg/kg/dose [SG-low-dose (LD) GH], or hGH at 1.0 mg/kg/dose [SG-high-dose (HD) GH] every other day for 28 days. Ten additional rats underwent sham operation and received water injections (sham control). After 28 days, SG-control and SG-LDGH rats weighed significantly less than the sham control group; the mean weight of the SG-HDGH group was not different from other groups. Weight per centimeter of the distal ileum was greater in all SG groups compared to the sham control group, and was greater in the SG-HDGH than in the SG-control group. Mean mucosal height of the distal ileum was greater in both SG groups receiving GH than in sham controls. No differences in ileal mucosal DNA content or ileal insulin-like growth factor-1 (IGF-1) content were identified between groups. Mucosal sucrase activity was not increased in hGH-treated rats. Serum calcium and phosphorus concentrations were higher in SG-HDGH rats than in SG-control animals. HDGH increased body weight, distal ileal weight/cm, and mucosal height in rats undergoing 75% small bowel resection. A trend toward normalization of serum calcium, phosphorus, and plasma IGF-1 concentrations was also observed. Further longer-term studies are indicated to learn if GH has a beneficial effect upon gut growth and function in the SG syndrome.