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Objective To investigate the effect of different doses of ketamine on inflammatory cytokines in rabbits with severe burn at early stage and preliminarily approach its regulatory action on early stage of inflammatory reaction due to stress of trauma.Methods Forty healthy male New Zealand rabbits were randomly divided into four groups in accord with the random number table method: normal control group, scald model group, ketamine analgesia group and ketamine anesthesia group. Before scald, pentobarbital sodium was used for anesthesia, afterwards catheters were inserted into internal jugular vein and internal carotid artery respectively ready for use, and 24 hours later, Ⅲ degree scald at the animal back and buttocks occupying 30% total body surface area (TBSA) was performed as the scald model for all the rabbits except those in normal control group. In ketamine analgesia group, after scald for 0.5 hour, 0.5 mg/kg ketamine intravenous injection was given to the rabbits as the loading dosage and then persistent intravenous pump infusion of 9μg·kg-1·min-1 ketamine was applied for all together 24 hours. In ketamine anesthesia group, after scald for 0.5 hour, 1.5 mg/kg ketamine intravenous injection was given to the rabbits, and then persistent intravenous pump infusion of 45μg·kg-1·min-1 ketamine was applied for 4 hours to maintain systemic anesthesia. In normal control and scald model groups, only intravenous infusion of equal amount of normal saline was given to the rabbits. The amount of intravenous transfusion in each group and the total dosages of ketamine used in ketamine analgesia group and ketamine anesthesia group were recorded. Before scald and 0.5, 6, 12, 24 hours after scald, arterial blood gas analyses were made, and the levels of serum interleukins (IL-1, IL-6) and tumor necrosis factor-α (TNF-α) were determined.Results Although the indexes of blood gas analysis were changed in the four groups, they were all in the normal range, showing that the respiratory function was in the normal range and indirectly reflecting that the circulatory function was also in the normal range, thus the effects on cytokines by factors of respiratory and circulatory functions were ruled out. The levels of IL-1, IL-6 and TNF-α before scald showed no statistically significant differencesamong the four groups (allP > 0.05). From 0.5 hour after scald, the levels of IL-1, IL-6 and TNF-α were markedly higher in model group than those of normal control group [IL-1 (ng/L): 30.27±0.93 vs. 13.79±1.11, IL-6 (ng/L): 47.22±1.49 vs. 46.31±4.12, TNF-α (ng/L): 243.39±20.85 vs. 190.95±14.97, allP < 0.05], and the situation continued until 24 hours after scald; the levels of IL-1, IL-6 and TNF-α from 6 hours after scald were significantly decreased in ketamine analgesia and ketamine anesthesia groups compared with those in the model group, and from 12 hours after scald, the degrees of descent in levels of the above indexes in ketamine analgesia group were more obvious than those in ketamine anesthesia group [IL-1 (ng/L): 19.28±2.51 vs. 40.12±10.31, IL-6 (ng/L): 52.10±4.23 vs. 72.20±10.11, TNF-α (ng/L): 246.03±20.74 vs. 313.71±27.34, allP < 0.05].Conclusion The low-dose ketamine analgesia and ketamine anesthesia have certain degree of inhibitory effect on the expression and release of inflammatory cytokines at the early stage in rabbits with severe burn, the effect of long-term low-dose ketamine analgesia being more significant.
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Objective To evaluate the protective effect of propofol on liver in severely scalded rabbits.Methods Twenty healthy male New Zealand rabbits, aged 3-4 months, weighing 2.3-2.5 kg, were randomly divided into either scald group (group S, n =10) or propofol group (group P, n =10).Thirty percent of the total body surface was shaved chemically with 10％ sodium sulphate and then exposed to 98 ℃ water for 20 s to produce third degree thermal injury at the back and buttocks of anesthetized rats.In group P, propofol was injected at a dose of 1.5 mg/kg at 1 h after scald, followed by an infusion of 4 mg· kg-1 · h 1 for4 h.The equal volume of normal saline was given in groupS.Before scald (T1), at 1 h after scald (T2) , and at 6, 12 and 24 h after administration of propofol or normal saline (T3-5) , blood samples were taken from the internal jugular vein for determination of serum alanine aminotransferase (ALT) activity (by lactate dehydrogenase method), aspartate aminotransferase (AST) activity (by MDH), and tumor necrosis factor-alpha (TNF-α) concentrations (by enzyme linked immunosorbent assay).The rabbits were sacrificed at T5, and their livers were removed and cut into sections which were stained with haematoxylin and eosin and examined under microscope.Results The serum ALT and AST activities and TNF-α concentrations were significantly higher at T2-5 than at T1.Compared with the values at T2, the serum ALT and AST activities and TNF-α concentrations in group S and serum TNF-α concentrations in group P were significantly increased at T3-5, and no significant change was found in the serum ALT and AST activities at T3-5 in group P.Compared with group S, the serum ALT and AST activities and TNF-α concentrations were significantly decreased at T3 5, and the pathological changes were mitigated in group P.Conclusion Propofol provides protective effect on liver in severely scalded rabbits.
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This study examined the effects of ursolic acid (UA) on the proliferation and apoptosis of a human ovarian cancer cell line, CAOV3. The CAOV3 cells were cultured in the RPMI 1640 media and treated with different concentrations of UA (0, 10, 20, 40 mumol/L). The proliferation rate of the CAOV3 cells was determined by MTT assay. The apoptosis rate was measured by flow cytometry. ERK activity was detected by immunoprecipitation and the expressions of p-ERK1/2, MKP-1, Bax and Bcl-2 by Western blotting. The results showed that the proliferation rate was significantly decreased in the cells treated with UA as compared with that in the non-treated cells (P<0.05). The intracellular ERK activity and p-ERK1/2 expression were also reduced in the UA-treated cells, while the MKP-1 expression was elevated. Moreover, the apoptosis was found in the CAOV3 cells exposed to UA; the Bax expression was increased and the Bcl-2 expression decreased. The apoptosis rate in the UA-treated cells was much higher than that in the non-treated cells (P<0.05). It is concluded that UA can inhibit the proliferation of CAOV3 cells by suppressing the ERK activity and the expression of p-ERK1/2. And it can also induce the apoptosis of the CAOV3 cells by up-regulating the Bax expression and down-regulating the Bcl-2 expression.