[An experimental study on the effects of early postburn nutrition on calcitonin gene--related peptide]

To explore the resuscitation effects of different nutritional routes during early postburn stage on intestinal tract, and the relationship between calcitonin gene -- related peptide (CGRP) and resuscitation of intestinal tract.

Sixty Wistar rats inflicted by 30% TBSA III degree flame burn were randomly divided into burn with enteral feeding group (EF, 30 rats) and burn with early parenteral nutrition group (EPN group, 30 rats). Six normal rats without burn injury served as control group (C). The changes in general condition, intestinal mucosal blood flow, plasma concentration of CGRP immunologic competence substance and intestinal CGRP positive staining substance in the rats were observed at 6, 12, 24, 48 and 72 postburn hours (PBHs).

The rat intestinal mucosal blood flow decreased postburn, especially in EPN group (P < 0.05). The postburn plasma CGRP increased and the plasma CGRP level in EF group was obviously lower than that in EPN group at 72 PBH (P < 0.01). The CGRP positive staining cells of intestinal tract decreased markedly postburn (P < 0.05) in both burn groups, and those in EPN were significantly lower abundant than those in EF group at 24 and 48 PBHs (P < 0.05). Furthermore, the decrease in intestinal mucosal blood flow was positively related to the decrease in intestinal intramuscular nerve plexus CGRP (r = 0.72, P < 0.05).

Enteral nutrition exerted better effects on early postburn intestinal resuscitation than parenteral nutrition. The decrease in intestinal blood supply might be mainly due to the excessive increase in plasma CGRP immune active substance and the decrease of postburn intestinal tract CGRP immunologic competence substance. Early enteral feeding might play resuscitative role by modulating CGRP.