1.Effects of norepinephrine on brain edema of rats with severe burn
Journal of Third Military Medical University 2003;0(18):-
Objective To investigate the effects of norepinephrine on brain edema of rats in 24 h after severe burn.Methods A total of 48 healthy Wistar rats were randomly divided into 8 groups: normal control group,1,2,5 mg/kg norepinephrine,burn group,burn with 1,2,5 mg/kg norepinephrine pretreatment groups(n=6 in each group).The rats in all burn groups were scalded into 40%TBSAⅢ degree burn.Pathological features were observed,and blood brain barrier,brain water(%) were examined in postburn 24 h.Results Pathological evidence of brain edema exhibited in the burn group and burn group with norepinephrine pretreatment,and increased permeability of blood brain barrier and brain water were observed.The burn with norepinephrine pretreatment groups were more significantly severe in comparison with simple burn groups and normal control group.Conclusion Norepinephrine may play an important role in brain edema in postburn 24 h,suggesting that stress of postburn may induce brain edema.
2.Effect of norepinephrine on expression of vascular endothelial growth factor of brain tissues in burn rats
Chinese Journal of Trauma 2003;0(10):-
Objective To investigate the effects of norepinephrine (NE) on vascular endothelial growth factor (VEGF) expression of brain tissues in severe burn rats. Methods The healthy male Wistar rats were made into 40%TBSAⅢ?burn models to observe the effect of NE on blood brain barrier. In the meantime, effect of NE was examined by means of immunocytochemistry and real time PCR. Results (1) Permeability of blood brain barrier was increased in burn and burn with NE stimulating rats, with significantly statistical difference compared with normal control group (P
3.APOPTOSIS AND CHANGES IN APOTOSIS REGULATING GENES IN LUNG TISSUE CELLS AFTER SMOKE INHALATION INJURY IN RATS
Wenjun LI ; Zongcheng YANG ; Xiaodon YANG
Medical Journal of Chinese People's Liberation Army 1983;0(02):-
To explore the role of apoptosis, apoptosis regulating genes in the pathogenesis and development of smoke inhalation injury. With smoke inhalation injury rat model, the changes int the expression of Bcl 2, Bax, Fas, FasL genes mRNA and protein contents and their relationship with apoptosis of lung tissue cells at different time points after the injury were observed with TUNEL, immunohistochemistry and RT PCR techniques. The results showed that: ①apoptosis indet of lung colls after smoke inhalation injury increased, ②expressions of Bcl 2, Bax, Fas, FasL genes were obviously up regulated in injury group, peaking at the 12th hour, whereas the peak of protein expression was at the 24th hour. Furthermore, a significant correlation was found between the expression of Fas, Fasl, Bax gene and apoptosis indices in lung cells. The results suggested that apoptosis participated in the early pathological process of smoke inhalation injury, and apoptosis regulating genes foot part in the regulation of apoptosis in smoke inhalation injury.
4.Analysis of up-regulated genes in human umbilical vein endothelial cells stimulated by lipopolysaccharide
Ziwen LIANG ; Zongcheng YANG ; Xiangdong LUO ;
Journal of Third Military Medical University 1983;0(04):-
Objective To screen and analyze genes up regulated in human umbilical vein endothelial cells (HUVEC) stimulated by lipopolysaccharide (LPS). Methods Suppression subtractive hybridization (SSH) was performed between the unstimulated HUVEC(driver) and HUVEC stimulated with LPS(tester) to generate subtractive cDNA library. The library was screened with colony dot hybridization to further verify the differentially expressed cDNA clones. Positive clones were sequenced and BLAST analyzed. The 3 novel cDNA sequences were verified by RT PCR. Results Twenty five up regulated genes related to inflammation, cellular cytoskeletal rearrangement, cellular proliferation and apoptosis, intercellular message transduction, and 3 new expression sequence tags (EST) were acquired. RT PCR indicated the expression of the new ESTs only in HUVEC stimulated by LPS. Conclusion SSH is a powerful technique of high sensitivity for the detection and clone of up regulated gene expressed in HUVEC stimulated by LPS, which may be helpful to clarify the mechanism of endothelial cells activation stimulated by LPS.
5.Changes of myocardial mitochondrial permeability transition pore and its mechanism in the early stage after severe burns
Wanyi LIANG ; Yuesheng HUANG ; Zongcheng YANG ;
Journal of Third Military Medical University 2003;0(18):-
Objective To investigate the changes of myocardial mitochondrial permeability transition pore(PTP) and its mechanism in the early stage after severe burns. Methods An experimental model of 30% TBSA full thickness skin scalding was established in rats. All rats were injected with deoxyglucose(DOG) before sacrifice. Myocardial mitochondrial DOG and cytochrome c content, Ca 2+ concentration([Ca 2+ ] m) and MDA content were determined. Results ① There were no obvious changes of mitochondrial DOG and cytochrome c content at 1 h after burns, but mitochondrial DOG increased evidently at 3, 6, 12 and 24 h after burns. Meanwhile, cytochrome c content was significantly lower than that of the control, being 68.8%, 50.0%, 77.1% and 72.9% of that in the control, respectively. ② [Ca 2+ ] m and MDA content were significantly higher than those of the control at 3, 6, 12 and 24 h after burns. ③ Mitochondrial DOG content was positively correlated with [Ca 2+ ] m and MDA content, respectively, after burns. Conclusion There is no obvious change in myocardial mitochondrial permeability transition pore, but PTP opening increases markedly at 3, 6, 12 and 24 h after burns. Mitochondrial Ca 2+ overloading and increase in free radicals may be the cause leading to PTP opening.
6.p38 kinase pathway mediated cardiomyocyte injury in rats due to hypoxia and burn serum
Jiaping ZHANG ; Yuesheng HUANG ; Zongcheng YANG ;
Journal of Third Military Medical University 2003;0(18):-
Objective To investigate the roles of the activated p38 kinase in cell injury by observation of the effects of hypoxia and burn serum on cardiomyocyte p38 kinase and JNK activation. Methods Phosphorylation of p38 kinase and JNK in primary cultured neonatal rat cardiomyocytes before and after hypoxia and burn serum was determined by Western blotting. Effects of pretreatment with SB203580 at the dose of 10 ?mol/L on the changes of phosphorylation of p38 kinase in cardiomyocytes, lactate dehydrogenase (LDH) activity, cell vitality and apoptosis were investigated, respectively. Results Exposure of rat neonatal cardiomyocytes to hypoxia and burn serum resulted in a rapid and long lasting activation of p38 kinase but no significant activation of JNK. SB203580(10 ?mol/l), a selective inhibitor of p38 kinase, could inhibit p38 kinase activation dramatically, decrease the LDH activity in culture media and cell apoptosis significantly and improve cell vitality. Conclusion In the two stress activated signal pathways of MAPKs family, p38 kinase pathway, but not JNK, is the major pathway activated by hypoxia and burn serum and participates in the cardiomyocyte injury.
7.Protective effects of diazoxide on cardiomyocytes after severe burn injury and the related mechanism
Wanyi LIANG ; Yuesheng HUANG ; Zongcheng YANG ;
Journal of Third Military Medical University 2003;0(19):-
Objective To investigate the protective effects of diazoxide on cardiomyocytes after severe burn injury Methods A total of 24 healthy Wistar rats were randomized into normal control group(Control), burn group(Burn) and diazoxide treated group(Diazo)( n =8) Rats in Burn and Diazo groups were inflicted with 30%TBSA Ⅲ degree burn and resuscitated with Ringer's solution intraperitoneally 30 min after burn Diazoxide was injected into rats in Diazo group at the dose of 10 mg/kg through the external jugular vein After rats were sacrificed at 6 h after burn, myocardial mitochondrial K + influx, respiratory function, Ca 2+ concentration ([Ca 2+ ]m), MDA content, serum CK and LDH levels were determined Results Mitochondrial K + influx of Diazo group was evidently higher than that in Control and Burn group Mitochondrial respiratory control rate(RCR) and ST 3 in Diazo group were higher than that in Burn group However, [Ca 2+ ]m, MDA, CK and LDH levels in Diazo group were significantly lower than those in Burn group Conclusion Diazoxide can attenuate the damage to cardiomyocytes after severe burn injury, which might be related to the opening of mitochondrial K + channel, inhibition of mitochondria from Ca 2+ overloading and decrease of free radical production
8.THE ROLE OF NF-?B ACTIVATION IN THE PATHOGENESIS OF SMOKE INHALATION INJURY AND THE EFFECTS OF DEXAMETHASONE ON IT
Wenjun LI ; Zongcheng YANG ; Tianpen JI
Medical Journal of Chinese People's Liberation Army 1982;0(01):-
The aim of the study was to explore the role of NF ?B activation in the pathogenesis of smoke inhalation injury and to evaluate the effects of dexamethasone on NF ?B activation. 130 Wistar rats were inflicted with smoke inhalation injury and randomized equally into the control group, smoke inhalation injury group and dexamethasone treatment group.The expressions of NF ?B P 65 ,I?B ?,TNF ?,and ICAM 1 proteins in the lung tissue were determined by immunohistochemistry at 2,6,12,24,48,72 hours after smoke inhalation injury. The results showed that,after smoke inhalation ,the expressions of NF ?BP 65 ,TNF ?,and ICAM 1 increased,whereas the expression of I?B ? decreased. In the dexamethasone treatment group,the expressions of NF ?BP 65 ,TNF ?,and ICAM 1 were down regulated, and I?B ? was up regulated.These results suggest that NF ?B activation may participate in the pathogenesis of smoke inhalation injury.Dexamethasone could suppress NF ?B activation, thus partially blocked the production of cytokines and adhesion molecules,and in turn reduced the damage of inflammatory response. Therefore NF ?B activation might be a key point in the development of smoke inhalation injury and modulation of activation of NF?B might be a potential therapeutic strategy to treat this injury at the transcription level.
9.CLONING OF LIPOPOLYSACCHARIDE RESPONSIVE GENES IN ENDOTHELIAL CELLS BY SUPPRESSION SUBTRACTIVE HYBRIDIZATION
Ziwen LIANG ; Xiangdong LUO ; Zongcheng YANG
Medical Journal of Chinese People's Liberation Army 1981;0(04):-
To screen genes in endothelial cells resulted from responding to lipopolysaccharide (LPS), mRNA was extracted from both untreated human umbilical endothelial cells (HUVEC) following and HUVEC which were treated with LPS for 6 hours. cDNAs of both populations were synthesized to generate cDNA libraries by suppression subtractive hybridization (SSH). The libraries were then screened with colony dot blots. Positive clones were sequenced and BLAST analysed. The results showed differential genes included 3 novel genes and 22 known genes. The 3 novel genes were confirmed by Northern blotting analysis. These 22 known genes were involved in the regulation of proinflammatory response, cell apoptosis, cytoskeleton, signal transduction and energy metabolism. These results suggest that SSH is an effective technique to detect differential gene expression in HUVEC, which may be helpful to evaluate molecular mechanisms of endothelial injury induced by LPS and provide potential therapeutic targets for LPS related disturbances.
10.STUDY ON THE MECHANISMS OF ABNORMAL SPA EXPRESSION AFTER SMOKE INHALATION INJURY
Zuhong FU ; Zongcheng YANG ; Zhenhon HU
Medical Journal of Chinese People's Liberation Army 1981;0(06):-
The aim of this study was to investigate the mechanism of abnormal SPA expression after smoke inhalation injury (SII).The rat model with SII was used to observe the expression of SPA and the level of H 2 O 2 in the lung tissue. EMSA was performed to study the effect of H 2 O 2 on the TTF 1 binding activity in regulating area of SPA gene. The results showed that H 2 O 2 was increased, and the expression of SPA was down regulated in lung tissue after smoke inhalation injury. H 2 O 2 could inhibit the TTF 1 binding activity in SPA regulating area in vitro . Our results suggested that the inhibition of TTF 1 activity by oxidative stress might be the mechanism of abnormal SPA expression after SII.