研究脑囊性动脉瘤壁胶原型及细胞成分的构成和分布、胶原代谢相关的细胞因子、金属蛋白酶的表达和细胞定位，以期明确脑囊性动脉瘤胶原代谢的特点。通过比较破裂、未破裂动脉瘤和正常脑动脉组织之间的差异，确定局部胶原代谢与脑囊性动脉瘤破裂的相关性，为进一步阐明脑囊性动脉瘤破裂的机制奠定理论基础。

Part ICerebral aneurysm is the malformation and regional dilation of the cerebral artery, presenting as a process of the artery wall. Most of the patients with aneurysm are middle-aged people ranging from 30 to 60 years old. 95% cerebral aneurysms are saccular aneurysms. According to the reports of recent epidemiological investigation, the rupture of cerebral aneurysm is the third cause of stroke. Moreover, the clinical features of aneurysm rupture are acute and sudden attack, quick deterioration and high mortality. And the key of management of aneurysm is to discover and treatment it as earlier as possible. Therefore, the research in etiology of saccular aneurysm has great significance in clinical diagnosis, prevention and treatment of this disease.There are three major assumptions about the formation of aneurysms, which including deficiency of tunica media, destruction of elastic tissues frame and retrograde changes of artery wall. A common pathway of these assumptions is that the formation of aneurysm is related tightly with the deficiency of regional structure of artery wall. The destruction of elastic fiber network is very important and perhaps the key factor in the process of aneurysm formation. Hence, most recent basic research in aneurysm formation and development and dilation are focus in this. In our work, 23 saccular aneurysms specimens from surgical resection are studied. Including 17 ruptured aneurysms and 6 unruptured aneurysms with 13 males and 10 females. The age of the patients is from 18 to 59 years old with mean age of 38 years. All the patients had done preoperative agiography (DSA) of all cerebral vessels and demonstrated the accuracy site of the aneurysms. Pterional approach was used and the sacs of the aneurysms were resected after clipping of the aneurysms' necks. Meanwhile, 7 cases of 'normal' cerebral artery from brain trauma were used as control.To study the differential distribution and expression of elastic fiber, type I,type II, type III and type IV collagen in the 'elastic-collagen network' of saccular aneurysmal wall and normal artery, the section of artery wall and aneurysmal wall were subjected to regular HE staining, immunohistochemical staining with collagen I,II,III,IV antibodies, and special staining of elastic fiber, Sirius-Red staining. All the results were analyzed and described.The primary conclusions including : 1. According to the observation of normal artery wall and aneurysmal wall, the internal elastic fiber, type I, type III and type IV collagen are defined as the basic structure of 'elastic-collagen network', this structure has an crucial role in the intact and stability of artery wall. 2. Accoding to the differential distribution and expression features of different components, this structure is divided to internal network (which consisted of internal elastic fiber and collagen IV) and external network (which consisted of collagen I and III). 3. Comparing with normal artery wall, all the aneurysmal walls have destruction of internal and external network whether they were ruptured or not. 4. The different degree of destruction in internal network of the ruptured and unruptured aneurysmal wall has a great significance, this damage is slighter in unruptured aneurysms. This result demonstrated that the internal network have a great impact on the formation and development of succular aneurysms. 5. The distribution of collagen I and III in the external network of aneurysm walls implies that the existence of a process in tissue and scar reconstruction of the collagen group. Further study need to be done to confirm this result. 6. The distribution of the pro-I and mature I collagen showed to be "separated", which may imply that the mature process from pro-I to I collagen could be checked. The reason is not clear and, of course, this conclusion needs to be confirmed by further studies.Part II.Intracranial saccular aneurysms (SA) is defined as a persistent localized dilatation on the vessel wall and is the main cause of the spontaneous subarachnoid hemorrhage. Anrurys