| Object: To study the effect of ascorbic acid on early brain injury(Early brain injury,EBI)and brain tissue protection in(subarachnoid hemorrhage,SAH)of rats with subarachnoid hemorrhage(SAH),and to establish the model of subarachnoid hemorrhage(SAH)in SD rats by secondary injection of blood into occipital cistern.The changes of water content in brain tissue of rats were observed.Methods: Forty-two clean adult SD male rats were selected as the subjects of this study.the body weight of each SD male rat ranged from 280 g to 300 g.They were randomly divided into three groups: sham operation group(sham group,n ? 14),SAH group(SAH group,n ? 14)and SAH+ ascorbic acid group(treatment group,n ? 14).The SAH model was established by secondary injection of blood into the occipital cistern.the Sham group was injected with the same amount of normal saline after successful puncture.in the treatment group,ascorbic acid 200 mg / kg was injected intraperitoneally after the modeling was successful.the animals were killed 24 hours later and the hippocampus was removed for detection.All animals were killed by cardiac perfusion,hippocampal tissue was taken out,labeled and fixed.Experimental methods: 1.Hematoxylin-eosin staining(HE staining)was used to observe the morphological changes of cortical brain tissue in different groups of rats.2.The apoptosis of neurons in cortical brain tissue of different groups of rats was detected by in situ end labeling(TUNEL).3.Immunohistochemical method was used to detect the expression of Bcl-2 and Bax in the cortex of different groups of rats.The results were statistically analyzed.Results:1.HE staining showed that the neurons in Sham group were arranged neatly,round or oval,with light staining and obvious nucleolus,while in SAH group,the neurons were crumpled and stained deeply,and there was nuclear fragmentation.In the treatment group,the number of neurons with pyknosis and deep staining was significantly decreased.2.In TUNEL:Sham group,only a very small number of neurons were positive for TUNEL staining.The number of apoptotic cells in SAH group was higher than that in Sham group(P< 0.05).The number of apoptotic positive cells in the treatment group was significantly lower than that in the SAH group(P< 0 05),and the number of apoptotic cells in the treatment group was higher than that in the Sham group(P< 0 05).3.Immunohistochemistry: the expression of Bcl-2 and Bax was lower in Sham group.The proportion of positive cells in SAH group was significantly higher than that in Sham group(P < 0.01).Compared with SAH group,the proportion of Bcl-2 positive cells in the treatment group was significantly higher and the expression of Bax was significantly lower than that in the treatment group,and the difference was significant(p< 0.01).The proportion of Bcl-2 and Bax positive cells in the treatment group was significantly higher than that in the Sham group(P< 0.01).Conclusion:1 There were no obvious TUNEL positive cells in the sham operation group,but the number of positive cells in the SAH group was significantly increased,and the number of apoptosis in the ascorbic acid treatment group was significantly lower than that in the SAH group.2 Immunohistochemical detection of apoptosis-related genes showed that compared with each group,the expression of apoptosis-promoting protein Bax decreased,the expression of anti-apoptosis protein Bcl-2 increased,and the number of apoptotic cells decreased significantly in ascorbic acid group.Therefore,ascorbic acid may play a protective role on EBI after SAH by promoting the expression of anti-apoptotic protein Bcl-2,inhibiting the level of pro-apoptotic protein Bax,increasing the ratio of Bcl-2 to Bax,and then inhibiting the apoptosis of neurons in brain tissue.3 Ascorbic acid may alleviate the early brain injury after subarachnoid hemorrhage by inhibiting the apoptosis of injured neurons in the early stage after subarachnoid hemorrhage in rats. |
PDF Full Text Request