[The influence of recombinant human growth hormone on the apoptosis and intestinal mucosal structure in severely scalded rats].

OBJECTIVE

To explore the influence of recombinant human growth hormone (rhGH) on the apoptosis and intestinal mucosal structure in severely scalded rats.

METHODS

Thirty male Wistar rats were randomly divided into three groups, i.e. control, scalding and rhGH groups. The rats in scalding and rhGH groups were inflicted with 25% TBSA III degree scalding on the back and immediately followed by intraperitoneal injection of dexamethasone (80 mg/kg). The scalded rats were administered with normal saline and rhGH (1.33 IU.kg(-1).d(-1)) since 2 postburn hours (PBHs), respectively in the last two groups. The changes of the apoptosis rate, the intestinal mucosal proliferative index (PI) and epithelial ultrastructure and the intestinal mucosal pathomorphology of the distal end of ileal mucosal tissue were observed on 30 and 96 PBHs.

RESULTS

The intestinal mucosa morphology and epithelia in scalding group were severely injured but were significantly ameliorated by rhGH to near those in control group. The PI in rhGH and scalding groups at 30 PBHs was evidently higher that that in control group (P < 0.05 - 0.01). But the PI exhibited no obvious difference between scalding and rhGH groups. While the PI in rhGH group at 96 PBHs was obviously higher than that in both scalding and control groups (P < 0.01). The intestinal mucosal epithelial apoptotic rate in scalding group was significantly higher than that in control group (P < 0.01), while that in rhGH group was evidently lower than that in scalding and control groups (P < 0.05 - 0.01).

CONCLUSION

rhGH could promote postburn intestinal mucosa epithelial proliferation in slow - action manner and inhibit intestinal mucosal epithelial apoptosis with rapid and obvious effects. As a result, the intestinal mucosal epithelial injury could be ameliorated by rhGH by means of its inhibiting roles and the normal morphological structure of intestinal mucosa was maintained ad hoc.