The Expression Of AQP4, Apoptosis-related Proteins And The Effects Of Nimodipine After Subarachnoid Hemorrhage In Rat Brain

Objective:Discussion the changes of Caspase-3,Bcl-2,Bax,AQP4mRNAand the influences of nimodipine after Subarachnoid Hemorrhage in rats,provides a theoretical basis for clinical prevention and treatment cerebral hemorrhage.Method:1. 40 Wistar rats were used and divided into 3 groups:sham operation group(n=8);SAH model group (n=8);The SAH+N group (n=8). Model preparation process:Uses 10% hydration trichloroacetaldehyde acetochloral (300mg/kg) abdominal cavity anaesthesia the wistar rats,fixed the rats in the experimental board, prone position, skin preparation of the Department of shearing,local iodine disinfection with ethanol.Incision skin in a hollow (the included angle forms by the cerebellum medulla oblongata)approximately 0.5cm next external occipital protubeRNAce, from external occipital protubeRNAce to axis, approximately 3cm, blunt separation of the skin and muscle on each floor,fully exposed atlas,that is,see the white tenacious atlanto -occipital membRNAe,coverage with normal saline gauze after full hemostasis.The sham-operation group injected into physiological saline 0.3ml to the cisterna magna;The SAH model group,injected into autologous blood 0.3ml two times,the blood was drawn from the ophthalmic venous plexus,to observe the rats breathing and heart rate changes. put back in the rats,and maintain prone position,the head low-300;The SAH model gives nimodipine treatment group injects into nimodipine 0.2mg/kg,in the SAH latter 30 minutes abdominal cavities.2. Using the neuroethology loeffler 5-point scale methods for evaluation. 5 points: When holds the back,the rats can normal movement,and stand up from failure in 5S;4 points:The independent movement reduces,and still turning over in 5S;3points:>5S turning over;2 points: Cannot stand up from failure;1 point: Cannot the movement.3. Before injection of blood ,and at the1st day and the 14th day after injection and nimodipine treats,Carries on skull Doppler supersonic to examine of rat basilar artery blood flow velocity of the largest for judgment the degree of cerebral vasospasm.4. The use of dry and wet method the quality of brain tissue water content.5. HE staining of rat brain stem after SAH cells changes in the structure of6. RT-PCR was used to analyze the expression of AQP4mRNA7. Western blotting was used to analyze the expression of Caspase-3,Bax,Bcl-2.Results:1. Rats SAHld neurological behavior score compared with the sham-operated group decreased; application nimodipine group score significantly higher.2. Transcranial Doppler ultrasound examinations showed: SAH1d basilar artery blood flow in rats in the sham-operated group compared to significantly speed up the application of nimodipine, the basilar artery flow velocity slowed down.3. Dry, wet brain tissue water content measurements showed that: SAH group of brain water content compared with the sham-operated group was significantly increased,application of nimodipine after SAH compared with brain tissue water content decreased significantly.4. HE staining showed that: SAH cerebral hyperemia, edema,significantly reduced the number of cells and scattered foci of hemorrhage,nimodipine group increase in the number of cells.5. SAH1d group of Caspase-3 protein expression compared with the sham group significantly increased ,application of nimodipine decreased significantly.6. SAH1d group of Bax/Bcl-2 compared with the sham group significantly increased ,application of nimodipine decreased significantly.7. SAH1d Group AQP4mRNA expression compared with sham-operated group decreased significantly and increased after application of nimodipine.Discussion:SAH cause great difficulties because of its high mortality and disability rate. Therefore,it is is very essential to establishes a kind,stable,the reliable animal model for Clinical treatment.The results of this study show that:â‘ In SAH1d group the expression of Caspase-3 obvious increased compared with the sham-operation group,the expression of Caspase-3 dropped in nimodipine group,the brain stem appeared apoptosis after brain injury,and treat with nimodipine the apoptosis was inhibited.â‘¡In SAH1d group expression of the ratio of Bax/Bcl-2 obvious increased compared with the sham-operation group,the expression of the ratio of Bax/Bcl-2 dropped in nimodipine group, Bcl-2 are the first step in apoptosis is also the most important aspect.Bcl-2 and Bax form a different polymer,Inhibition of cytochrome C release from mitochondria,by lower permeability and direct role in the type of CED-4 molecules,thereby inhibiting the activation of Caspase-9 to Caspase-3 can not be activated to prevent apoptosis.â‘¢Compared with the sham-operated group, SAH1d group significantly decreased the expression of AQP4mRNA,application of nimodipine significantly increased,combination of brain water content and the results of HE staining of brain injury and brain edema is closely related to the reduction of AQP4 expression,Nimodipine increases the expression of AQP4 to some extent reduced the occurrence and development of cerebral edema.Conclusion:1. Neurological behavior score in rats significantly lower,basilar artery blood flow velocity significantly accelerated increased,brain water content and the number of neurons significantly reduced on the success SAH model of rats .2. SAH brain injury is related with increased Bax/Bcl-2 ratio, Caspase-3 increase in brain cells caused apoptosis.3. SAH brain injury is related with decreased AQP4 and increase cerebral edema.4. Nimodipine has obvious protective effect of the brain, which may be related to a direct reduction of Caspase-3 expression and the Bax/Bcl-2 ratio, apoptosis inhibition, but also may reduce the increase in the expression of AQP4-related cerebral edema.