S. Coerper et al., Insulin-like growth factor I accelerates gastric ulcer healing by stimulating cell proliferation and by inhibiting gastric acid secretion, SC J GASTR, 36(9), 2001, pp. 921-927
Background: Given the importance of Insulin-Like Growth Factor I (IGF-I) to
intestinal maintenance and the presence of IGF-I in salivary glands, we hy
pothesized that IGF-I participates in the healing of gastric ulcers. The ai
m of the study was to determine: 1) whether IGF-I applied locally would sup
port gastric ulcer healing by increasing cell proliferation and 2) the effe
ct of IGF-I on gastric acid secretion. Methods: Gastric ulcers were induced
with a cryoprobe. Immediately thereafter, IGF-I (0.4, 4.0 and 40 mug) or v
ehicle was infiltrated perifocally. In another group, animals received a da
ily dose of 40 mu mol omeprazole subcutaneously. Ulcer healing was evaluate
d by ulcer size and histological examination at 7 days. Pentagastrin-stimul
ated gastric acid secretion was evaluated in conscious rats with gastric fi
stula, after IGF-1(400 mug) had been injected intravenously. Results: IGF-I
significantly reduced ulcer size, but only at low doses (0.4 mug/kg body w
eight (BW), P = 0.008; 4 mug/kg BW, P = 0.001). This effect was similar to
omeprazole treatment. Histological examination after IGF-I administration s
howed increased cell proliferation, increased IGF-I content and down-regula
ted IGF-I receptors. The secretory studies demonstrated a significant decre
ase in gastric acid secretion 30 min after IGF-I bolus injection (IGF-I: 53
+/- 11 mu Eq; vehicle: 116 +/- 5 mu Eq; P = 0.001), which lasted for more
than 1 h. Conclusion: IGF-I stimulates gastric ulcer healing, stimulating c
ell proliferation and inhibiting gastric acid secretion.