Role of HMGB1 in Post-traumatic Endoplasmic Reticulum Stress in Rat Lung Tissues / 法医学杂志

OBJECTIVES@#To explore the role of high mobility group B1 （HMGB1） protein in the post-traumatic endoplasmic reticulum stress （ERS） in rat lung tissues.@*METHODS@#The rat model of acute lung injury was established by crushing the hind limbs of rats with standard weight. The first experiment was to divide rats into postural control group and crush groups （6 h, 18 h and 30 h after crushing）. The second experiment was to divide rats into postural control group, 18 h crush group, HMGB1 inhibitor sodium butyrate （SB） group and 18 h crush+SB group. The protein expression changes of HMGB1 and ERS- related proteins （GRP78, caspase-12, CHOP and IRE1α） in rat lung tissues were detected with Western blotting. Meanwhile, the pathological changes of rat lungs were observed by HE stain.@*RESULTS@#Compared with the postural control group, the expression levels of ERS-related proteins （GRP78, caspase-12, CHOP and IRE1α） and HMGB1 protein in rat lung tissues by crushing the hind limbs of rats were obviously increased. The protein levels reduced at 30 h after crushing but were still higher than those of postural control group and obvious pathological changes of acute lung injury were observed simultaneously in rats. Compared with the 18 h crush group, the expression levels of the ERS-related proteins and HMGB1 protein in rat lung tissues were attenuated in 18 h crush+SB group, and the pathological changes of rat lung injury began to alleviate.@*CONCLUSIONS@#HMGB1-ERS pathway activated by traumatic stress can lead to acute lung injury in rats.

Optic Nerve Crush Induces Changes of Hydrogen Sulfide Synthases Expression in the Rat Retina / 法医学杂志

Objective To investigate the expression changes of the hydrogen sulfide synthases cystathionineγ-lyase (CSE), cystathionineβ-synthase (CBS), and 3-mercaptopyruvate sulfurtransferase (3-MST), after optic nerve crush (ONC) in rat the retina.Methods The rat model of ONC was established.Rats were divided into normal control, ONC, and sham control groups.Histopathologic changes in retina, the number of retinal ganglion cells (RGC) and retinal thickness of inner part (RTIP) were measured.The changes of CSE, CBS and 3-MST mRNA expression were detected with quantitative real-time PCR.Results The retinal histostructure was normal in normal controls and with minor changes in sham controls, respectively.Compared with sham group, significant retina damages were found in the ONC group:a time-dependent reduction of RGC number and RTIP.Expressions of CSE, CBS and 3-MST mRNA in rat retina were detected in normal control.Compared with normal controls, the expressions of CSE, CBS and 3-MST mRNA did not show any significant changes in the sham controls.Compared with sham controls, CBS mRNA expressions showed a time-dependent increase at 3 d, 7 d and 14 d after crush in the ONC group;CSE mRNA expressions increased to the peak at 3 d and then slightly reduced at 14 d after crush;3-MST mRNA expressions showed the trend of increase at 3 d and 7 d and then enhanced remarkably at 14 d after crush.Conclusion Hydrogen sulfide synthases CSE, CBS and3-MST expressions were up-regulated in rat retina following ONC, which may cause an increase in local endogenous hydrogen sulfide production in the retina and a compensatory protective effect.

The Role of Hydrogen Sulfide in Acute Liver Injury Induced by Traumatic Stress in Rats / 法医学杂志

OBJECTIVE@#To explore the role of hydrogen sulfide (H2S) in acute liver injury induced by crushing hind limbs of rats.@*METHODS@#The rats were randomly divided into the following groups: control, crushing, H2S donor sodium hydrosulfide (NaHS) + crushing, H2S inhibitor propargylglycine (PAG) + crushing group. The acute liver injury model was established by 'crushing the hind limbs of rats with standard weight. Rats were sacrificed at 30 min and 120 min after the crush. The activities of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured by colorimetric method, and the content of H2S in plasma and the contents of malondialdehyde (MDA), protein carbonyl, glutathione (GSH) in the liver and the activity of H2S generating enzyme (cystathionine y-lyase, CSE) were determined by chemical method. The expression of CSE mRNA in liver was detected by RT-PCR.@*RESULTS@#For crush injury group, the levels of AST and ALT in serum, MDA and protein carbonyl in liver increased. The levels of GSH, CSE, CSE mRNA in liver and H2S in serum decreased. The administration of NaHS before limbs crush could attenuate the changes of liver injury, but the pre-treatment with PAG could exacerbate the changes.@*CONCLUSION@#The decrease of H2S production could involve in mediating the acute liver injury induced by traumatic stress in rats.

Effects of HO-1 on Lipopolysaccharide-induced Endoplasmic Reticulum Stress of Rat Hepatocytes / 法医学杂志

OBJECTIVE@#To investigate effects of antioxidant stress protein heme oxygenase-1 (HO-1) on lipopolysaccharide (LPS)-induced endoplasmic reticulum stress (ERS) of rat hepatocytes.@*METHODS@#The BRL cells (rat hepatocyte cell line) were cultured. The hepatocytes were treated with LPS, LPS+HO-1 siRNA, HO-1 siRNA and PBS solution, respectively. The cell viability was measured by trypan blue exclusion test. The apoptosis cells were detected by the fluorescent dye Hoechst 33258. Expressions of GRP78, CHOP, caspase-12 and HO-1 were detected by Western blotting.@*RESULTS@#LPS caused an increase of HO-1 protein expression of rat hepatocytes in a dose-dependent and time-dependent manner, a up-regulation of GRP78, CHOP and caspase-12, a decrease in cell viability, and an increase in apoptosis rate of hepatocytes. Pretreatment of HO-1 siRNA inhibited the up-regulation of LPS-induced HO-1, however, aggravated ERS and cellular injury.@*CONCLUSION@#HO-1 inhibites ERS-mediated cellular injury of rat hepatocytes induced by LPS.

Nitric oxide mediated TNF-α, IL-1β gene expression in liver induced by crush injury of rat's soft tissues / 法医学杂志

OBJECTIVE@#To explore the effect of nitric oxide (NO) on the gene expression of hepatic TNF-α and IL-1β by crush injury of rat's soft tissues.@*METHODS@#Rats were randomly divided into sham group, crush group, crush+aminoguanidine (AG) group, and crush+L-arginine (L-Arg) group. Activities of ALT and AST as well as NO level in serum were measured. Gene expressions of TNF-α and IL-1β were detected with RT-PCR.@*RESULTS@#Obvious increase in TNF-α and IL-1β mRNA expression was detected in the crush group compared with the sham group (P<0.05). After pretreated L-Arg, expressions of TNF-α and IL-1β mRNA were markedly increased (P<0.05). After pretreated AG, those indices obviously decreased (P<0.05). Activities of ALT and AST enhanced and NO level increased in the crush group compared with the sham group (P<0.05). Pretreatment with L-Arg or AG led to substantial increased or reduced activities of ALT and AST as well as NO levels, respectively.@*CONCLUSION@#Endogenous NO mediated TNF-α, IL-1β mRNA up expression in liver induced by increased production of NO after crush injury of rat's soft tissues.

Expression of CaMK II delta in cerebral cortex following traumatic brain injury / 法医学杂志

OBJECTIVE@#To observe the time-course expression of calcium-calmodulin dependent protein kinase II delta (CaMK II delta) in cerebral cortex after traumatic brain injury (TBI).@*METHODS@#The TBI rat model was established. The expression of CaMK II delta in cerebral cortex around injured area was tested by Western blotting and immunohistochemical staining.@*RESULTS@#Western blotting revealed expression of CaMK II delta in normal rat brain cortex. It gradually increased after TBI, peaked after 3 days, and then returned to normal level. The result of immunohistochemical staining was consistent with that of Western blotting.@*CONCLUSION@#The expression of CaMK II delta around injured area after TBI increased initially and then decreased. It could be used as a new indicator for wound age determination following TBI.

Negative modulation of NO for diaphragmatic contractile reduction induced by sepsis and restraint position / 法医学杂志

In practice of forensic medicine, potential disease can be associated with fatal asphyxia in restraint position. Research has demonstrated that nitric oxide (NO) and nitric oxide synthase (NOS) are plentifully distributed in skeletal muscle, contributing to the regulation of contractile and relaxation. In the current study, respiratory functions, indices of diaphragmatic biomechanical functions ex vivo, as well as NO levels in serum, the expressions of diaphragmatic inducible NOS (iNOS) mRNA, and the effects of L-NNA on contractility of the diaphragm were observed in sepsis induced by cecal ligation and puncture (CLP) under the condition of restraint position. The results showed that in the CLP12-18h rats, respiratory dysfunctions; indices of diaphragmatic biomechanical functions (Pt, +dT/dt(max), -dT/dt(max), CT, Po, force over the full range of the force-frequency relationship and fatigue resistance) declined progressively; the NO level in serum, and iNOS mRNA expression in the diaphragm increased progressively; force increased significantly at all stimulation frequencies after L-NNA pre-incubation. Restraint position 1 h in CLP12 h rats resulted in severe respiratory dysfunctions after relative stable respiratory functions, almost all the indices of diaphragmatic biomechanical functions declined further, whereas little change took place in NO level in serum and diaphragmatic iNOS mRNA expression; and the effects of L-NNA were lack of statistical significance compared with those of CLP12 h, but differed from CLP18 h group. These results suggest that restraint position and sepsis act together in a synergistic manner to aggravate the great reduction of diaphragmatic contractility via, at least in part, the negative modulation of NO, which may contribute to the pathogenesis of positional asphyxia.

Changes of MDA, SOD, TNF-alpha, and IL-1beta in rat brain tissue after concussion / 法医学杂志

OBJECTIVE@#To observe the changes of malondialdehyde (MDA), superoxide dismutase (SOD), tumor necrosis factor-alpha (TNF-alpha), and interleukin-1beta (IL-1beta) in rat brain tissue and to explore the mechanism of secondary cerebral injury after brain concussion.@*METHODS@#The brain concussion model was established with the pathological changes of rat brain tissue by Weil stain. The expressions of MDA and SOD in brain tissue were examined by photochemical method. The expressions of TNF-alpha and IL-1beta in cerebral cortex and hippocampus were examined by immunochemistry.@*RESULTS@#Nerve myelin sheath showed disorder, disruption, gryposis and swelling by Weil stain. Above changes were more severe at 12h. The quantity of MDA in rat brain tissue after concussion was significantly higher than that in the control group. The activity of SOD was significantly lower than that in the control group. The expressions of TNF-alpha and IL-1beta increased more significantly in cerebral cortex and hippocampus in rat brain tissue after concussion than that in the control group.@*CONCLUSION@#Oxidative stress and inflammatory injury in the rat brain tissue, which may play an important role in secondary cerebral injury after concussion.

Endoplasmic reticulum stress mediates lipopolysaccharide-induced apoptosis in rat hepatocyte / 法医学杂志

OBJECTIVE@#To investigate the role of endoplasmic reticulum stress (ERS) in lipopolysaccharide (LPS)-induced hepatocyte apoptosis.@*METHODS@#Cells of the rat hepatocyte line BRL were cultured. The hepatocytes were treated with LPS, ERS inducer thapsigargin (TG), and ERS inhibitor 4-phenylbutyric acid (4-PBA), respectively or in their different combination. The cell viability was measured by MTT assay. The cyto-nuclear morphological changes of apoptosis cells were detected by the fluorescent dye Hoechst 33258. The apoptosis rate was assessed by flow cytometry with Annexin V-FITC/PI double-staining. Expressions of GRP78 as ERS marker protein, CHOP, caspase-12 and cleaved-caspase-3 as ERS related protein were detected by Western blotting.@*RESULTS@#LPS could cause a decrease in cell viability and an increase in apoptosis rate in a dose- and time-dependent manner. The expression of GRP78, CHOP, caspase-12 and cleaved-caspase-3 proteins were significantly increased with LPS treatment. TG led to a marked decrease in cell viability and an increase in apoptosis rate, which aggravated the hepatocyte injury induced by LPS; whereas 4-PBA alleviated LPS-induced apoptosis.@*CONCLUSION@#ERS mediates LPS-induced hepatocyte injuries, indicating that ERS may play a vital role in the pathogenesis of LPS-induced hepatocyte injuries.

Myocardial expression of Spry1 and MAPK proteins of viral myocarditis / 法医学杂志

OBJECTIVE@#To discuss the myocardial expression of Spry1 and MAPK proteins of viral myocarditis (VMC), to reveal its mechanism of sudden death, and to provide guides for forensic identification of sudden cardiac death.@*METHODS@#Thirty Balb/c male mice were randomly divided into VMC group and control group, inoculated intraperitoneally with Coxsackievirus B3 and Eagel's solution, respectively. After the mice were sacrificed, the cardiac tissues of the mice were taken to proceed regular pathological examination. The changes of Spry1 protein, Spry1 mRNA and MAPK protein were detected by immunohistochemistry, Western blotting and real-time PCR.@*RESULTS@#Under light microscope, the pathologic changes included myocardial interstitial edema, inflammatory cells infiltration, myocardial necrosis, and focal and patchy necrosis of myocardial fiber in VMC group. The expression of Spry1 protein in VMC group was lower than that in control group (P < 0.05). There was slightly decreased expression of Spry1 of the mRNA level in VMC group (P > 0.05). But the MAPK protein expression in VMC group was higher than that in control group (P < 0.05).@*CONCLUSION@#The pathway of MAPK/ERK involving Spry1 protein accelerates the expression of collagen, which may contribute to arrhythmia, heart failure and even sudden cardiac death.

Effects of restraint position on changes of diaphragmatic mechanical characteristic in rats / 法医学杂志

OBJECTIVE@#To observe effects of restraint position on the changes of diaphragmatic mechanical characteristic in rats, and try to explore the role of nitric oxide (NO).@*METHODS@#Rat model of restraint position was established. Rats were divided into control group, restraint position 12h and 24h groups. The markers of respiratory functions in vivo and the biomechanical markers of diaphragmatic characteristic ex vivo were evaluated. Serum NO levels were measured with spectrophotometry. The expressions of nNOS and iNOS mRNA in diaphragm were detected using RT-PCR.@*RESULTS@#Compared with control group, respiratory rate, tidal volume and minute ventilation were significantly decreased in the restraint position 12h and 24h groups. Pt of diaphragm significantly decreased and force-generating capacity reduced at low frequency stimulation in 12h group. Force-generating capacity over the full range reduced at low and high frequency stimulation in 24h group. Pt of diaphragm in control and restraint position groups increased after L-NNA pre-incubation. Force-frequency relationship after L-NNA pre-incubation reduced in 24h group. NO level in serum increased significantly in the restraint position groups. Diaphragmatic nNOS mRNA expression was upregulated significantly in the restraint position groups.@*CONCLUSION@#Restraint position induces the decreasement of diaphragmatic contractility and the decreasement is mediated by NO from diaphragm or circulation blood.

Effect of soft tissue crush injury on tensions of thoracic aortic rings in rats / 法医学杂志

OBJECTIVE@#To observe the effect of soft tissue crush injury on the tensions of thoracic aortic rings (TARs) in rats and to investigate the potential roles of nitric oxide in the change of the tensions.@*METHODS@#Thirty adult SD rats were randomly divided into control group and crush injury (8 h and 16 h after injury) groups. Two kinds of TARs (one with endothelium and the other without endothelium) in vitro were prepared. In the TARs with endothelium, the tensions induced by phenylephrine (PE), acetylcholine (Ach), calcium ionophore A23187 and angiotensin II (AngI) were measured by the vascular tension detective technique. Then the TARs with endothelium were preincubated with nitric oxide synthase inhibitor N-nitro-L-arginine (L-NNA) for 20 minutes, the tensions induced by PE and Ang II were measured again. In the TARs without endothelium, the tensions induced by PE and Ang II were measured by the same method.@*RESULTS@#In the TARs with endothelium, the tension of relaxation induced by cumulative doses of Ach and A23187 decreased significantly in 8 h and 16h groups. The tension of contraction induced by cumulative doses of PE and Ang II also decreased significantly (P<0.05). The tension of contraction increased after the preincubation with L-NNA. In the TARs without endothelium, the tension of contraction induced by PE and Ang II increased comparing to that of TARs with endothelium.@*CONCLUSION@#The soft tissue crush injury can influence the tensions of TARs in rats and the vascular-derived NO can mediate the effects.

Change of nitric oxide in local muscle of crush injury hind-limbs in rats / 法医学杂志

OBJECTIVE@#To investigate the change of nitric oxide (NO) level in local muscles induced by crushing hind-limbs in rats.@*METHODS@#The rat experimental model of hind-limb crushing injury was established by crushing the hind limbs of rats with standard weight for 5 hours, thereafter releving the standard weight for another 5 hours. The rats were randomly divided into sham group, crushing group, crushing and injecting aminoguanidine (AG) group, crushing and injecting L-arginine (L-Arg) group. The NOS activity and NO level in local muscles and serum were spectrophotometrically measured, and iNOS and eNOS protein expressions in local muscles were examined by immunohistochemistry. The weight ratio of wet to dry (W/D) of local muscles was measured and the pathologic changes were observed.@*RESULTS@#The crushing hind-limbs induced serious primary and secondary injuries of local muscles such as rupture and rhadomyolysis of skeletal muscular fibers, interstitial vascular congestion and edema, and marked increase in W/D. The expressions of eNOS and iNOS were upregulated in local muscle in crush group compared with sham group. The NOS activity and NO level in local muscles and serum significantly increased. There was positive relationship between NO level and W/D in local muscles. With the usage of AG and L-arg, the hind-limb injuries seemed alleviated and aggravated, respectively.@*CONCLUSION@#The crushing hind-limbs of rats elicited the upregulation of eNOS and iNOS protein expression, the enhancement of NOS activity and the excess production of NO, the latter of which was involved in the mediation of secondary pathological changes in local muscles.

Mechanism of acute liver injury induced by crushing hindlimbs in rabbits / 法医学杂志

OBJECTIVE@#To investigate the role of oxidative stress in acute liver injury during crushing hindlimbs in rabbit.@*METHODS@#The crushing injury model in rabbit was established by intermittent crushing the hind limbs of rabbit with standard weight. The ALT and AST activities were spectrophotometrically measured. The weight ratio (wet/dry,W/D) of livers was measured with scale, and the pathologic changes were observed. Superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and total anti-oxidant capacity (T-AOC) as well as malondialdehyde (MDA) level were spectrophotometrically measured.@*RESULTS@#As compared with control rabbits, crushing hindlimbs of rabbits induced acute liver injury with the increase in ALT and AST activities in serum,which were 4.31 (P < 0.01) and 10.54 times (P < 0.01) of control group respectively, there were cellular swellings and slight congestion of hepatic sinuses. In addition,crushing hind-limbs elicited significant decrease in SOD,CAT,GSH-Px activity and T-AOC to 17%, 29%, 24% and 21% (P < 0.01) compared with control group respectively, whereas MDA level markedly enhanced.@*CONCLUSION@#Crushing hindlimbs of rabbits induced acute liver injury and significant decrease in anti-oxidant capacity, the latter maybe play an important role in crushing hind-limbs of rabbits-elicited the acute liver injury.

Polymorphic analysis of four Y short tandem repeat loci in Han nationality of Hebei province in China / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the distribution of the polymorphism of the Y-chromosomal loci DYS438, DYS439, GATA A7.1 and GATA A7.2 among Han population in Hebei province.</p><p><b>METHODS</b>With the use of PCR followed by polyacrylamide gel electrophoresis and silver staining, the allele frequencies of these loci in 164 unrelated men of Han population were investigated.</p><p><b>RESULTS</b>Four, five, five, four alleles were observed at the loci DYS438, DYS439, GATA A7.1 and GATA A7.2 respectively; the frequencies of these alleles ranged from 0.0359 to 0.6587, from 0.0179 to 0.4107, from 0.0122 to 0.4146 and from 0.0476 to 0.5238 respectively; the probability discrimination of these loci were 0.5121, 0.6811, 0.6679 and 0.6327 respectively. Seventy different haplotypes were found at these loci. Thirty-six different haplotypes appeared only once. The power of discrimination of these four loci was 0.9480.</p><p><b>CONCLUSION</b>The results demonstrate that these loci(DYS438, DYS439, GATA A7.1 and GATA A7.2) are good genetic markers with high determination power and can be applied to individual identification, especially in paternity test and the detection of mixed samples.</p>

Effects of cholecystokinin-octapeptide on the tension of pulmonary artery in rabbits with endotoxic shock / 生理学报

For investigation of the regulatory mechanism of cholecystokinin-octapeptide (CCK-8) on pulmonary circulation in rabbits with endotoxic shock (ES) induced by lipopolysaccharides (LPS), mean arterial pressure (MAP) and pulmonary arterial pressure (PAP) were evaluated for 5 h in five groups of rabbits: group of LPS (8 mg/kg, i.v.)-induced ES, group of CCK-8 pretreatment (15 microg/kg, i.v.) 15 min before LPS administration (8 mg/kg, i.v.), group of proglumide pretreatment (1 mg/kg, i.v.) 15 min before LPS administration (8 mg/kg, i.v.), group of CCK (15 microg/kg, i.v.) only, and normal saline (control) group. The pulmonary arterial tension was measured with isolated vascular ring technique. The results showed that LPS-induced pulmonary arterial hypertension was abolished by CCK-8. In contrast, proglumide, a nonspecific antagonist of CCK-8 receptor, potentiated the deleterious effect of LPS. The contractile response of isolated pulmonary artery to alpha-adrenoceptor agonist phenylephrine (PE) was enhanced and the relaxation response to acetylcholine (ACh) was depressed significantly after LPS was injected, but the effect could be reversed by CCK-8. These results suggest that pulmonary circulation is improved by CCK-8 in ES, and the regulatory effects of CCK-8 may be brought about by modulating the pulmonary arterial tension.

Effect of peroxynitrite on the reactivity of rabbit pulmonary arteries in vitro / 生理学报

To investigate the effect of peroxynitrite (ONOO(-)) on the reactivity of rabbit pulmonary artery, the responses of rabbit pulmonary artery rings (PARs) pre-incubated with ONOO(-) to endothelium-dependent and receptor-dependent relaxants ACh and ADP, endothelium-dependent and receptor-independent relaxant calcium ionophore A23187, endothelium-independent relaxant sodium nitroprusside (SNP) and alpha(1)-adrenoceptor agonist phenylephrine (PE) were observed in vitro in an accumulative manner. (1) Relaxations of PARs to ACh, calcium ionophore A23187 and ADP were markedly impaired with shift of accumulative dose-response curve of each agonist to the right. Inhibition of endothelium-dependent and receptor-dependent or independent relaxation by ONOO(-) was dose-dependent. (2) ONOO(-) incubation inhibited SNP-induced relaxation in a dose-dependent manner. (3) Contractile response of PARs to PE varied with the different doses of ONOO(-). In PARs pre-incubated with 0.5 mmol/L ONOO(-), contractile response was significantly enhanced with shift of PE accumulative dose-response curve to the left, whereas in PARs pre-incubated with 1.0 mmol/L or 2.0 mmol/L ONOO(-), it was markedly reduced with right shift of PE accumulative dose-response curve. (4) Vehicle of ONOO(-) had no effect on responses to each agonist.Decomposed ONOO(-) had minimal effect on the response to PE and ADP, in contrast, relaxation of PARs to ACh, A23187 and SNP were enhanced. These results indicate that ONOO(-) may contribute to regulatory disorder of pulmonary artery reactivity.

Endogenous peroxynitrite mediates lipopolysaccharide-induced injury in cultured pulmonary artery endothelial cells / 生理学报

This study, using cultured bovine pulmonary artery endothelial cells (BPAECs), was undertaken to investigate the roles of endogenous ONOO(-) in LPS-caused injury in endothelial cells. The fluorescent intensity of nitrotyrosine (NT), a specific marker of ONOO(-) generation, in BPAECs represented the content of endogenous ONOO(-) generation. The fluorescent intensity of NT and the number of NT positive cells were detected with flow cytometry (FCM), and the percentage of NT positive cells was calculated. The results are as follows. (1) LPS (1, 5 and 10 microg/ml) caused a marked increase in fluorescent intensity of NT in a dose-dependent manner, which was significantly increased compared to the vehicle group (P<0.01).The number and percentage of NT positive cells were markedly increased (both P<0.05 vs vehicle group). Aminoguanidine (AG), a selective inhibitor of inducible nitric oxide synthase (iNOS), inhibited LPS-induced increase in fluorescent intensity of NT in BPAECs. However, the number and percentage of NT positive cells had a tendency to reduce. (2) LPS brought about an enhancement in MDA content and the activity of LDH in cultured supernatant. AG reversed the enhancement in MDA content induced by LPS (P<0.01). In contrast, AG had a marginal effect on the activity of LDH. (3) LPS induced an increase in apoptotic rate in BPAECs in a dose-dependent manner. The number of apoptotic cells markedly increased as well. Some BPAECs stained with fluorescent probe ethidium bromide showed morphological features of apoptosis with chromatin condensation and nuclear fragmentation. AG reduced the apoptotic rate and the number of apoptotic cells, both of which were still higher than those of vehicle group (P<0.05). LPS led to inhibition of mitochondrial respiration and membrane potential in an accumulation manner. In conclusion, LPS caused injury to cultured BPAECs and increased the production of ONOO(-).The cytotoxicity of LPS may be mediated by the endogenous ONOO(-).