Effect of pure carbachol or combined with dietary fiber on intestinal mucosal barrier of rats after diffuse brain injury / 中国中西医结合急救杂志

ABSTRACT

Objective To study the protective effect of pure carbachol or combined with dietary fiber on intestinal mucosal barrier of rats after diffuse brain injury (DBI).Methods An adult male Wistar rat model of DBI was reproduced by gravitational shock method. The rats injured and survived after resuscitation were divided into three groups model group (n = 40), carbachol group (n = 40) and carbachol combined with dietary fiber group (combined group,n = 32). In addition, a control group was established by simply an incision performed on the scalp, and the rats could drink freely (n = 5). In the experimental groups, 2 hours after resuscitation the rats began to receive gavage, 6 hours once, the liquid amount 15 mL/kg should be assured in every 6 hours, and if insufficient, normal saline was supplemented. In model group, normal saline 90 mL/kg was given, in carbachol group, carbachol 300μg/kg was administered and in combined group, carbachol 300μg/kg combined with dietary fiber 60 mL/kg was supplied. At 3 (combined group being excluded), 6, 12, 24 and 48 hours after resuscitation, the rats were anesthetized to collect samples and detect the plasma levels of D-lactate and activity of diamine oxidase (DAO) respectively, and the changes of villus height of small intestine were examined by a light microscope.Results The plasma D-lactate levels and the activities of DAO at any time point in the experimental groups were significant higher than those in control group (allP < 0.01). Along with the prolongation of time, the levels of plasma D-lactate and DAO activities in carbachol and carbachol plus diatary fiber groups were gradually lower than those of the model group, and at 48 hours after injury they reached their valley values [D-lactate (ng/L) 6.32±0.79, 7.46±1.67 vs. 17.65±1.53, DAO activity (kU/L) 0.76±0.01, 0.86±0.01 vs. 2.23±0.15]. Under light microscopy, compared with control group, the villus height of small intestinal mucosa at any time point in any experimental group was gradually lowered, and reached the valley values at 12 hours, then gradually increased , and peaked at 48 hours, the villus height in carbachol group and combined group was higher than that in model group (μm 265.36±10.20, 261.54±10.38 vs. 247.51±9.39, bothP < 0.05).Conclusion When only carbachol is administered into the rat intestine early after diffuse brain injury in rats, beginning from 6 hours after injury, the protective effect of intestinal mucosal barrier is shown, representing decrease of plasma D-lactate level and DAO activity, amelioration of intestinal mucosal damage and protection of intestinal mucosal barrier; under the same above situation, the carbachol combined with dietary fiber was applied, showing the similar above carbachol protective effects.