| Objective: To study the expression of HO-1 and c-fos in the main organs of respiratory system,nervous system and circulatory system after acute carbon monoxide poisoning(ACMP),and to explore its application value in forensic science.Methods: Fifty SD healthy male rats were randomly divided into control group(n=10)and acute carbon monoxide poisoning group(n=40).Acute carbon monoxide poisoning group was treated with modified Thom SR method to make rat acute carbon monoxide poisoning model.In the carbon monoxide poisoning group,a high-purity carbon monoxide gas with a concentration of 99% is injected into the poisoning cylinder,and the concentration of carbon monoxide in the cylinder is controlled by a carbon monoxide gas detecting tube to be between 3000 ppm and 4000 ppm,and then the awake rat is put into the poisoning.In the cylinder,the rats were inhaled with carbon monoxide gas for 30-40 minutes.The rats were anesthetized at 3h,6h,12 h and 24 h after poisoning.The experimental control group directly placed the rats in the poisoning tank for 30-40 minutes without introducing carbon monoxide gas.The pathological changes of heart,brain and lung tissues were observed by hematoxylin-eosin staining.The expressions of HO-1 and c-fos proteins were observed by SABC immunohistochemistry and Western-Blot detection.Statistical analysis was conducted to investigate the changes and sensitivity of HO-1 and c-fos in heart,brain and lung tissues in acute carbon monoxide poisoning.Results: 1.The results of HE staining under light microscope showed that compared with the experimental control group,the brain tissue of acute carbon monoxide poisoning showed hypoxia,brain tissue loose and edema,microvascular and telangiectasia,congestion,inflammatory cell infiltration,and nerve fiber swelling.Compared with the experimental control group,the lung tissue became thinner and the alveolar space was dilated,and there was a slight break.Inflammatory cells infiltrated in various layers of the bronchus,and a large number of red blood cells were seen in the alveolar space.No obvious abnormalities were found in myocardial fibers.2.The expression of ho-1 c-fos protein was detected by immunohistochemistry.:(1)Compared with the control group,c-fos protein in the carbon monoxide poisoning group had a large number of positive cells,mainly expressing alveolar epithelial cells,alveolar wall lymphocytes and vascular endothelial cells,reaching a peak at 3h(p<0.05),and Time-related expression;It is mainly expressed in the nucleus of nerve cells in brain tissue,and can be expressed in positive cells at 3h,peaked at 12h(p<0.05),and expressed in a time-dependent manner.The myocardium was mainly expressed in the nucleus of myocardial cells,which was brownish yellow granules,which reached a peak at 6h(P<0.05)and correlated with time.(2)HO-1 protein showed a downward trend in lung tissue(P<0.05).The carbon monoxide poisoning group was statistically significant compared with the experimental control group,mainly expressed in alveolar wall,bronchial wall cells and lymphocytes,neutrophils.There is also positive expression in cells as well as in macrophages.HO-1 showed an upward trend in brain tissue.The carbon monoxide poisoning group was compared with the experimental control group to obtain P<0.05,which mainly expressed around the nucleus of nerve cells,and a small amount of positive expression particles were observed in the nucleus.HO-1 expression in cardiomyocytes was not obvious,and a small number of positive cells were not significantly different from the experimental control group(P>0.05).3.The results of Western-Blot showed that:(1)c-fos protein in the carbon monoxide poisoning group compared with the experimental control group showed an upward trend(P<0.05),3h large expression and peak(P<0.05),6h slightly After 12 hours of decline,it increased again(P<005),and decreased at 24h(P<0.05)showed a “double peak trend”.The expression trend of c-fos protein in myocardium and brain tissue was similar to that in lung tissue,which was a “bimodal trend”,but the peak time was delayed,the myocardial rose to the peak at 6h(P<0.05),and the peak of brain tissue appeared at 12 h.(P<0.05).(2)The expression of HO-1 in lung tissue decreased with the prolongation of carbon monoxide poisoning(P<0.05),P<0.05 in the experimental control group and carbon monoxide poisoning group.There was an upward trend in brain tissue(P<0.05),and the experimental control group was P<0.05 compared with the carbon monoxide poisoning group.There was less expression of HO-1 in the myocardium,and there was no significant difference in expression between the groups(P>0.05).Conclusions: In this experiment,based on the establishment of acute carbon monoxide poisoning model in rats,the normal control group was used.The poisoning group was divided into 3h group,6h group,12 h group and 24 h group according to different survival time.The heart,brain and lung were observed in each group.Pathological changes were made to investigate the expression trends of HO-1 and c-fos proteins.1.Compared with the experimental control group,the changes of brain and lung in the carbon monoxide poisoning group were larger,showing acute hypoxic changes,and no obvious abnormalities were found in the myocardium,indicating that the brain and lung tissues were greatly affected by acute carbon monoxide poisoning,and the response was obvious.2.Compared with the experimental control group,the expression trends of c-fos protein in the heart,brain and lung tissues were similar,that is,they all showed a "bimodal trend",but their expression phases and peaks were different,indicating that each organ was poisoned by carbon monoxide.The start-up time of the reaction and stress states is different.The results of immunohistochemistry showed that the expression of HO-1 in the lungs of carbon monoxide poisoning was different from that of other types of hypoxic lung tissues,suggesting that the hypoxic state caused by carbon monoxide poisoning and other types of hypoxia injury mechanisms different;The expression of HO-1 in the lung is also inconsistent with that in other types of hypoxic lung tissue,showing a downward trend,indicating that the expression of HO-1 in lung tissue may be inhibited by carbon monoxide gas.On the contrary,HO-1 is in the brain.There is an upward trend in the organization.This provides a new idea for the prevention and treatment of early lung injury and carbon monoxide poisoning delayed encephalopathy in acute carbon monoxide poisoning,and the forensic identification and time inference of carbon monoxide poisoning is also of great significance. |
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