Effect of somatotropin on skin wound healing in rats

Somatotropin, in addition to having an anabolizing effect, also acts on the healing process by accelerating the local formation of granulation tissue and collagen synthesis and deposition when administered subcutaneously (SC). Objective: To evaluate the effect of somatotropin on skin wound healing in rats. Methods: Fifty-three male Wistar rats aged on average 145.19 days and weighing 287.27 g at the beginning of the study were divided into two groups: control (n=26) receiving 1.2 ml/day distilled water (SC), and experimental (n=27) receiving 0.2 IU/kg/day human somatotropin (SC). A skin wound was produced in the dorsum of the animal and measured daily, and wound contraction was calculated at the end of the experiment. At 3, 7 and 14 days, blood was collected from 9 animals in each group for biochemical determination of plasma proteins and the wound was resected for histological study. Epithelialization, local inflammatory reaction, granulation tissue, neovascularization and fibrosis were evaluated microscopically. Results: The calculation of wound contraction at the 3 checking times dis not show significant differences between the control and experimental groups. The biochemical determinations showed an decrease in total proteins (p=0.007) and a increase in the albumin/gobulin ratio (p=0.03) in the control group on the 14th day of the study, whereas remain stable in the experimental group. Histological evaluation showed a significant increase in fibrosis in the experimental group on the 7th day (p<0.0001). Conclusion: Somatotropin remain stable the albumin/globulin ratio and total plasma proteins on the 14th day, and also intensified cicatricial fibrosis when used for 7 days.

Somatotropin; Wound healing

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