OBJECTIVETo observe the changes in motilin (MTL), substance P (SP), vasoactive intestinal peptide (VIP) and somatostatin (SS) in plasma of rats with severe scald injury at early stage and the effect of rheum on their changes.

METHODSEighty-eight Wistar rats were randomly divided into normal control group (NC, n = 8), scald group (S, gavage of distilled water after full-thickness scald, n = 40), therapeutic group (T, gavage of rheum solution after full-thickness scald, n = 40). The blood samples were harvested from inferior vena cava at 6, 12, 24, 48, 72 post scald hours (PSH) to determine the levels of MTL, SS, SP and VIP with radioimmunoassay.

RESULTS(1) The levels of MTL and SP were (198 +/- 28), (61 +/- 10) ng/L, respectively, in NC group. The levels of MTL and SP in S group reached their minimum values [(110 +/- 15), (30 +/- 5) ng/L, respectively] at 6 PSH, then ascended slowly, peaked at 72 PSH but still lower than those in NC group (P < 0.05). The levels of MTL and SP slowly descended in T group, reached normal levels at 48 PSH, and obviously higher than those in NC group at 72 PSH [(232 +/- 32), (73 +/- 11) ng/ L, respectively, P < 0.05], which were higher than those in S group at 6 -72 PSH. (2) The levels of VIP and SS were (35 +/- 6), (30 +/- 5) ng/L, respectively, in NC group. The levels of VIP and SS in S group were (70 +/- 12), (49 +/- 9) ng/L at 6 PSH, which were obviously higher than those in NC group (P < 0.01), then descended slowly, but still higher than normal level at 72 PSH (P < 0.05). The levels of VIP and SS in T group ascended slowly, reached the normal level at 48 PSH, which were lower than those in S group at each time points, and VIP reached peak value at 12 PSH.

CONCLUSIONRheum may regulate secretion and release of gastrointestinal hormones to plasma in rats with severe scald injury at early stage.