The purpose of this study was to examine the effect of growth hormone (GH) on the division and migration of the small intestinal epithelium in mice.
Twenty mice(ICR), weighing initially about 10 g, aged 18 days were randomly subdivided in two groups of control and GH-treated group.
Control group was sacrificied at 2hr, 2, 3, 4 and 5 day after intraperitoneal injection of ³H-thymidine (³H-TdR, 4μ Ci/gm of BW/day for 2 days). GH-treated group was injected subcutaneously with somatotropin(10 IU/mouse/day for 4 days) from 2 day ago of first ³H-TdR injection and then was sacrificied at 2hr, 2, 3, 4 and 5 day after intraperitoneal injection of ³H-TdR(4μ Ci/g of BW/day for 2 days).
The small intestines were collected for autoradiogrophy and Hematoxylin counterstain. The location of the labeled epithelial cells (LEC) in villi of the small intestine was invested with light microscope.
l. In the control group, the LEC regions in the small intestine were located at crypts on 1 dsy, at 0% ∼15.9±3.6% of villus high value(VHV) on 2 day, at 0%∼49.8±16.5% of VHV on 3 day, at 0%∼95.3±6.9% of VHV on 4 day and 62.9±6.7∼100% of VHV on 5 day, respectively.
2. In the GH-treated group, the LEC regions in the small intestine were located at crypts on 1 day, at 0%∼39.2±9.5% of VHV on 2 day, at 0%∼81.5±18.2% of VHV on 3 day, at 45.2±11.5%∼100% of VHV on 4 day, at 85%∼100% of VHV on 5 day, respectively.
3. VHV of tops in the LEC regions appeared to be 23.3% and 31.7% higher on 2 and 3 day, and VHV of the LEC region bases appeared to be 45.2%, 22.1% higher on 4 and 5 day, respectively in the GH-treated group than those observed in the control group. These difference was very highly significant (p<0.01)
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