Study On Relation Between The Changes Of TPA & MMP-9 Expression And Traumatic Subarachnoid Haemorrhage In Brain Of Fuddled Rats

Background and objectiveTraumatic subarachnoid haemorrhage(TSAH) accounted for 90% of intracalvariumhaemorrhage without skull fracture. In 1963, foreign scholar firstly reported that there wasrelationship between alcohol and TSAH. Most of death cases of TSAH after drinking, were dueto the slight violence (such as box) on the faces or (and) necks, and the injury of the brain wasslight. There is still no agreement or systematic studies on the mechanism of TSAH and theinfluence degrees of alcohol on it, which somewhat obstruct forensic analysis on the cause of thedeath and the adjudgement.We successfully established the model of TSAH on the fuddled mice, and proved that theTSAH was easily caused by slight beating after fuddled. Therefore, we start our research onobserving the expression of tPA and MMP-9 in the brain tissue of fuddled mice, and primarilydiscuss the possible relationship between drinking and the happening of TSAH as well as death.Methods and materialHealthy male SD mice, with the weight of250～350 g were grouped into acute fuddled teamand chronic fuddled team. Sure water was used instead of alcohol in the control group. Theedible alcohol of Erguotou of Peking(56％v/v)was injected into mice's stomach throughesophagus. The acute team was injected alcohol by 15 ml/kg for one time; the chronic team isinjected by 2 times per day at 8 hours' intervals, 8 ml/kg each time in the first 2 weeks and 12ml/kg each time in the next 2 weeks for one month in total. The same amount of pure water wasused in the control group. The research used self-made iron of simple pendulum duplicateapparatus of brain injury to duplicate the mice's model of closed cerebral trauma which has thephenomenon of go-by obstruction of brain's function two hours later after the injection in acuteteam and the last injection in the chronic team. We acquired the blood by cutting the mice's headafter beating at 0.5thh, 2thh, 4thh, 6thh, 12thh in acute team and at 2thh in chronic team, with eachteam including 7 mice in acute fuddled and 17 mice in chronic fuddled and 5 mice in injected water. Observe the changes of mice's vital sigh; detect the concentration of the ethanol in theblood and dye the brain tissue by HE and immunohistochemistry to observe the changes ofhistomorphology and the expression of tPA and MMP-9, and the data tested with SPSS statisticsoftware and Excel database.Results1. Observing the fuddled animal's behaviorsThe mouse appeared fever pitch, got around, Instability of gait a few minutes after drinking,and appeared some clinical manifestation of acute alcoholism such as lying on the side, hypnody,body-righting reflex disappearing a half hour after drinking. The respiration lowers(P＜0.05); theblood pressure lowers (P＜0.05). But, the blood pressure raised for a while after hitting. Mice 2weeks after injected in the chronic group were foodless and the hair becomes rough and dim; thespirit becomes frustrated. 3 weeks after injected, mice were weightless (P＜0.05), 4 weeks afterinjected, the basal blood pressure steps up (P＜0.05).2. Detecting the concentration of ethanolThe acute group's concentration of ethanol reach the high-peek of 188.8±5.8 mg/dl at the2thh after injected, and then step down gradually to 1.7±0.5 mg/dl at the 12th hour.3. TSAH's incidence rate and death rateThe TSAH's incidence rate and death rate are 28.6％and 0 in acute group and 82.4％and58.8％in chronic group. The SAH's incidence rate and death rate are 0 in acute group and 5.9％and 0 in chronic group.4. HEIn morphology, the acute group's brain showed slight congestion and swelling to differentextent in each section of time. In histology, the arachnoids were rarities, congestion and swellingand tiny, punctiform SAH can be seen. The neuron and the microlia were slightly injured, whichwas mainly slightly hydropic degeneration (graininess swelling). One month after the lastdrinking in chronic group, the mice's brain showed congestion and swelling to different extent(from middle to severe), and SAH to different extent. In histology, the arachnoids were rarities,congestion and swelling, and SAH can be seen. The neuron was highly and widespread hydropicdegeneration or ballooning degeneration, and sporadic neuron necrosis was accompanied, andneuroglial cells widely hyperplasy. 5. IHCThe expression of tPA in brain tissue of normal mice was feeble. In the acute group, thepositive cells and the integral optical density (IOD) of MMP-9 and tPA in the hippocampus,cerebellum, and the occipital lobe raised gradually with the different sections of time(P＜0.05),and reached the high-peek at the 6th hour, which was higher than the control group(P＜0.05).There was no difference in frontal lobe compared with the control groups'. In chronic group,both of the positive cells and IOD of tPA were stronger than those in the control group (P＜0.01);the IOD of MMP-9 were higher than those in the control group (P＜0.01).Conclusions1. The experiment successfully established the stable model of TSAH on the fuddled mice,and proved that there were correlations between TSAH's higher incidence rate and death rate,and slight violent beating after fuddled.2. We proved that the blood pressure raise in chronic drinking mice, but the blood pressure ofpost-drinking mice lowed that of pre-drinking mice, and the blood pressure of post-hitting micewas temporary higher than one of pre-hitting mice. It was easily for blooding.3. The positive cells and the integral optical density of MMP-9 and tPA in the hippocampus,cerebellum, and the occipital lobe in acute fuddled mice were higher than the control groups. Thepositive cells and the integral optical density of MMP-9 and tPA in the hippocampus, cerebellum,the frontal lobe, the occipital lobe in chronic fuddled mice were higher than the control groups. Itmanifested that massive tPA was released in the early time of injury, destroy the structure ofvessal wall, which made it easy to disrupting and bleeding. The excessive expression of tPA aftermassive and long drinking would destroy the neuron.tPA has being used as a drug in the clinic to treat SAH and cerebral thrombosis in the acutestage. This study also showed that we should try the best to reduce the release of tPA and inhibitits activity to reduce the risk of another bleeding while treating the patients of TSAH afterdrinking. In the meanwhile, we should also pay attention to avoid the nonreversible neuroninjury.