High Salt Intake Induced Intracerebral Hemorrhage In Spontaneously Hypertensive Rats And The Morphological Comparative Of Autologous Blood Injection Rat Model

Background and Purpose:Intracerebral hemorrhage(ICH)is a non-traumatic hemorrhage that occurs in the brain parenchyma,the causes include high blood pressure,vascular malformations,vascular amyloidosis,aneurysm and so on.The incidence rate,lethality and disability is high,and the highest incidence is ethnic Asian.Risk factors include increased blood pressure,dyslipidemia,diabetes,smoking,alcohol,drugs,lifestyle and environment etc.Every year because of this disease give patients and families with a huge mental and economic burden.hypertension is one of the most important risk factor and causes of Cerebral hemorrhage,Long-term chronic high blood pressure can lead to pathological changes in blood vessels,when blood pressure increasing,especially when suddenly increasing,it can lead to cerebral vascular rupture and then cerebral hemorrhage occuring.With further research,many clinical studies found that high salt intake have a close relationship with the cerebral hemorrhage,but the experimental studies is not much.A large number of clinical and experimental studies have confirmed that high salt intake is an important cause of hypertension.High salt intake is first caused elevated blood pressure then caused cerebral hemorrhage,or directly effects on cerebral blood vessels then lead to cerebral hemorrhage,there are still many controversial.At present,there are two animal models of cerebral hemorrhage used widely.That are autologous blood inject or bacterial collagenase inject into brain parenchyma to simulate cerebral hemorrhage.The advantages of these two models are the time,location and the bleeding volume are easy to control.But the disadvantage is it difficult to simulate the process of cerebral hemorrhage and continuous bleeding process in patients.Therefore,to explore a new cerebral hemorrhage animal model to simulate the process of cerebral hemorrhage and the continuous state is important for the prevention of the occurrence of the cerebral hemorrhage.In this study,spontaneous hypertensive rats(SHR)and normotensive rats(WKY)were induced by high salt diet to induce spontaneous cerebral hemorrhage,The cerebral hemorrhage and brain microvascular architecture were observed in two kinds of rats.And compared with autologous blood injection model,In order to clarify the relationship between high salt intake,hypertension and cerebral hemorrhage,to provide an experimental basis for establishing a new animal model of intracerebral hemorrh age.Materials and Methods:6-week-old male SHR and WKY were randomly divided into high-salt diet group and Normal salt concentration feed group,The tail artery Systolic blood pressure was measured once a week.Behavioral changes were observed and neurological scores were recorded,rat survival was recorded,HE staining was used to observe the characteristics of hematoma after intracerebral hemorrhage,the brain water content was measured by wet-dry mass ratio method,evans blue(EB)detection of blood-brain barrier permeability,the changes of cerebral microvessel were observed by immunofluorescence staining,the ultrastructure and tight junction of brain microvessel were observed by transmission electron microscope.Autologous blood inject into the rat brain basal ganglia to establishment the autologous blood-brain hemorrhage model,And compared the morphological with the high salt induced SHR cerebral hemorrhage,observing the characteristics of living cerebral hemorrhage though magnetic resonance,the histological characteristics of cerebral hemorrhage were observed by HE staining,the ultrastructural changes of brain microvasculature were observed by transmission electron microscopy(TEM).Results:1.High salt intake resulted in increased blood pressure and cerebral hemorrhage in SHR and WKY rats,and increased blood pressure and hemorrhage in SHR,with more bleeding volume and hemorrhage.2.high salt intake can lead to increased vascular permeability;3.high salt intake can lead to decreased vWF and Claudin-5 expression;4.high salt intake can damage the structure of cerebrovascular wall and cerebral vascular endothelium tight junction;5.The main similarities and differences between the autologous blood injection cerebral hemorrhage model and high salt intake induced SHR cerebral hemorrhage are: HE staining can cause two kinds of cerebral hemorrhage hematoma at the tissue shrinkage rupture,different points are:the bleeding volume of the latter is small than the former,Bleeding position uncertain,Bleeding into a circular bleeding point,the cerebrovascular wall showed obvious damage,uneven thickness and mitochondria swelling.Conclusion:1.High salt intake can cause increased blood pressure in rats,brain microvascular structure changes,hypertension can increase the rat brain microvascular injury,the two can jointly promote the occurrence of cerebral hemorrhage in rats;2.The model of SHR cerebral hemorrhage induced by high salt intake can be used as an animal model to explore the mechanism of cerebral hemorrhage and the mechanism of high salt and cerebral vascular injury.