OBJECTIVETo study the effects of the panthenol-glutamine on intestinal damage and motor function of intestine in rats with burn injury as well as its dose-effect relationship.

METHODS(1) Experiment 1. Ninety SD rats were divided into groups A-I according to the random number table, with 10 rats in each group. Rats in groups A-I were inflicted with 30% TBSA full-thickness burn and fed by gavage with panthenol and glutamine at post injury hour (PIH) 4, in the whole dosage of 1.00 and 4, 0.50 and 4, 0.25 and 4, 1.00 and 2, 0.50 and 2, 0.25 and 2, 1.00 and 1, 0.50 and 1, 0.25 and 1 g·kg(-1)·d(-1). The feeding was carried out twice a day to achieve the total dosage in 7 days. On drug withdrawal day, blood and intestinal tissue were harvested to detect the intestinal propulsion index, diamine oxidase (DAO) activity in serum, and the content of acetylcholine and intestinal mucosa protein. The best proportion of panthenol and glutamine was screened. (2) Experiment 2. Seventy SD rats were divided into normal control (NC), burn (B), burn+panthenol (B+P), burn+glutamine (B+G), and burn+low, moderate, or high dose of panthenol-glutamine (B+LPG, B+MPG, B+HPG) groups according to the random number table, with 10 rats in each group. Rats in the latter 6 groups were inflicted with 30% TBSA full-thickness burn. Rats in the latter 5 groups were fed by gavage with panthenol and (or) glutamine at PIH 4. Rats in group B+P were fed with panthenol for 1 g·kg(-1)·d(-1), rats in group B+G with glutamine for 4 g·kg(-1)·d(-1), rats in groups B+LPG, B+MPG, and B+HPG with panthenol and glutamine in the dosage of 0.50 and 2, 1.00 and 4, 2.00 and 8 g·kg(-1)·d(-1). The feeding was carried out twice a day to achieve the total dosage for 7 days. The indexes and time point for observation were the same as those of experiment 1. Meanwhile, the pathological change in intestine was observed. The same process was carried out in the rats of group NC. Data were processed with factorial designed analysis of variance (ANOVA), one-way ANOVA and Fisher's exact probability test. LSD was applied for paired comparison.

RESULTS(1) The values of intestinal propulsion index and intestinal mucosa protein content in groups A and B were close (with P values all above 0.05), and were significantly higher than those of the other 7 groups (with P values all below 0.01). Content of acetylcholine in group A was significantly higher than that of the other 8 groups (with P values all below 0.01). DAO activity in groups A, D, and E was close in value (with P values all above 0.05), and all of the values were significantly lower than those of the other 6 groups (with P values all below 0.01). The best proportion of panthenol and glutamine was 1.00 and 4 g·kg(-1)·d(-1). (2) Compared with those of group NC, the intestinal propulsion index, the contents of acetylcholine and intestinal mucosa protein were decreased significantly, while the DAO activity obviously increased in group B (with P values all below 0.01); the intestinal propulsion index was decreased significantly in group B+P (P < 0.01); the intestinal propulsion index and content of acetylcholine were decreased significantly in group B+G (with P values all below 0.01); the intestinal propulsion index was decreased significantly in group B+LPG (P < 0.01); no obvious change was observed in groups B+MPG and B+HPG (with P values all above 0.05). Compared with those of group B [0.50 ± 0.07, (69 ± 10) µg/mL, (26 ± 11) µg/g, (0.672 ± 0.145) U/mL], the contents of acetylcholine and intestinal mucosa protein were increased significantly, DAO activity decreased significantly in group B+P (with P values all below 0.01); the contents of intestinal mucosa protein was increased significantly, DAO activity decreased significantly in group B+G (with P values all below 0.01); the contents of acetylcholine and intestinal mucosa protein were increased significantly in group B+LPG (with P values all below 0.01); the intestinal propulsion index, the contents of acetylcholine and intestinal mucosa protein were increased significantly, while the DAO activity obviously decreased in groups B+MPG and B+HPG [0.66 ± 0.07, 0.68 ± 0.05; (163 ± 24), (168 ± 15) µg/mL; (57 ± 7), (57 ± 7) µg/g; (0.203 ± 0.070), (0.193 ± 0.068) U/mL, with P values all below 0.01]. The levels of the four indexes in groups B+MPG and B+HPG were close or the same in values (with P values all above 0.05). Compared with those of group B, the numbers of rats with irregularly arranged villi in group B+P were decreased significantly (P < 0.05); the numbers of rats with villi decreased in height, irregularly arranged villi, and neutrophil infiltration in group B+G were decreased significantly (with P values all below 0.05); the numbers of rats with villi decreased in height, irregularly arranged villi, degeneration and necrosis of cells, and neutrophil infiltration in group B+LPG were decreased significantly (with P values all below 0.05); the numbers of rats with villi decreased in height and number, irregularly arranged villi, degeneration and necrosis of cells, and neutrophil infiltration in groups B+MPG and B+HPG were decreased significantly (with P values all below 0.05). There was no statistically significant difference between group B+HPG and group B+MPG for the former mentioned five indexes (with P values all above 0.05).

CONCLUSIONSCombined application of panthenol and glutamine can obviously reduce intestinal mucosa damage and promote gastrointestinal motility of rats with burn injury, and they show curative effect superior to exclusive use of either of the two drugs. The best proportion of panthenol and glutamine is 1.00 and 4 g·kg(-1)·d(-1).