The Study Of Extracranial-intracranial Arterial Sclerosis And It's Effect On The Cognitive Function

Arterial sclerosis is the most common disease among old people . In the elderly , more and more people would have cerebrovascular disease. Extracranial -intracranial arterial sclerosis is a main risk factor of cerebrovascular disease. The relationship between carotid arteriosclerosis and cognitive dysfunction is increasingly aroused people's attention .The study on extracranial-intracranial arterial sclerosis function included an clinical study and an experimental study: (1) To investigate the characteristic of extracranial-intracranial arterial sclerosis and the relationship with cognitive dysfunction; (2) To explore the pathologic characters and mechanism of carotid arteriosclerosis, and the cognitive dysfunction in old rats.Part One A clinical study of extracranial-intracranial arterial sclerosis and it's effect on the cognitive functionObjectives The report focused on investigating the characteristic of extracranial-intracranial arterial sclerosis and the relationship with cognitive dysfunction in elderly people through a random sample investigate.Methods From 2005 Oct to 2008 Feb, 2115 participants , aged 65 years old and over, were random selected from the inpatients and outpatients in our hospital. All participants were screened with digital subtraction angiography (DSA), CT angiography(CTA) or ultrasonography(US) and a baseline screening . Participants classified as with extracranial-intracranial arterial (311 patients) and without extracranial- intracranial arterial sclerosis(1804 patients) based on the result of imaging examination. At baseline screening, the following data were collected: demographic data , blood serum inflammatory factors tests (IL-6,TNF-аand Hs-CRP)and neuropsychological test (including MMSE, ADL, FOM, RVR, POD, DS subtest and BS subtest).Results(1) The baseline characteristics The baseline characteristics of the subjects were compared according to the existence of extracranial-intracranial arterial sclerosis. Compared with subjects without extracranial-intracranial arterial sclerosis, those with extracranial-intracranial arterial sclerosis had older age (p<0.05), lower education(p<0.01) ,higher BMI(p<0.01), higher systolic blood pressure and diastolic blood pressure (p< 0.01), higher fasting plasma glucose, Triglyceride and uric acid (p< 0.01).The distribution of diabetes and hyperuricemia in the patients with extracranial-intracranial arterial sclerosis were more higher than subjects without(P < 0.01). Extracranial- intracranial arterial sclerosis were more frequent in women(52.09% vs 47.91%).(2)The characters of extracranial-intracranial arterial sclerosis Extracranial- intracranial arterial sclerosis are more frequently happened to the extracranial of internal carotid artery(39.87%),vertebral artery(15.11%), then to ubclavical artery(10.29%),intracranial of internal carotid artery(8.04%),basilar artery(6.43%),middle cerebral artery(6.11%),and the common carotid artery (5.14%).Among them , The distribution of left middle cerebral artery, left vertebral artery and left ubclavical artery were more than those in right(P<0.01).311patientents with extracranial-intracranial arterial sclerosis were more frequent in women(52.09% vs 47.91%).(3)Compared with without extracranial-intracranial arterial sclerosis group, the expression of IL-6,TNF-Аand Hs-CRP increased significantly in the blood serum in extracranial-intracranial arterial sclerosis group(P<0.05).(4) Multivariate analysis for the association between risk factors and the occurrence of extracranial-intracranial arterial sclerosis After correcting confusing factors including demographic data and some diseases , the following risk factors including age,fasting plasma glucose,uric acid,systolic blood pressure and LDL were associated with the occurrence of extracranial-intracranial arterial sclerosis.(5)The relationship between extracranial-intracranial arterial sclerosis and cognitive dysfunction Compared with the group without extracranial-intracranial arterial sclerosis ,extracranial-intracranial arterial sclerosis have lower scores in MMSE,RVR,DS and BD(P<0.01),higher score in ADL(P<0.05).Patients with extracranial-intracranial arterial sclerosis and hyperuricemia had higher scores in MMSE(P<0.05),FOM and RVR (P<0.01)than those people who with extracranial-intracranial arterial sclerosis but hyperuricemia. when extracranial-intracranial arterial sclerosis have diabetes ,their scores in subentry of MMSE were lower than those without diabetes(P<0.01).Conclusions(1) Extracranial- intracranial arterial sclerosis are more frequently happened to the extracranial of internal carotid artery,vertebral artery,ubclavical artery,intracranial of internal carotid artery,basilar artery . The distribution of left middle cerebral artery, left vertebral artery and left ubclavical artery were more than those in right.(2) Age,fasting plasma glucose,uric acid,systolic blood pressure and LDL were associated with the occurrence of extracranial-intracranial arterial sclerosis .(3)The elderly people with extracranial-intracranial arterial sclerosis have more cognitive dysfunction than those without.Part two A experimental study of carotid atherosclerosis and the relationship with the cognitive dysfunction in old ratsObjectives: To investigate the histological characters of carotid in different age of rats , explore the pathologic change of carotid atherosclerosis and the relationship with the cognitive dysfunction in old rats.Methods 30 rats were divided into three groups :youth, manhood and agedness. Each group has 10 rats. Observed the microstructure and ultramicrostructure of the carotid endotheliocytal and hippocampus . Testing the expression of inflammatory factors in blood serum. Each rat Was evaluated in ethology to observed for the change of cognitive function.Results(1) The histological characters of old rat's carotid endotheliocyte Compared with the youth group, the aged rat's carotid endotheliocytal were badly destroyed, appeared hyperplasia and desquamation. Each structure of the carotid were unclear. The expression of TNF-αprotein and mRNA, IL-6 protein and mRNA in aortic wall were increased along with the age increased.(2) Compared with the group of youth, the expression of ICAM-I and TNF-αin blood serum were increased in the group of manhood(P<0.05);the expression of Hs-CRP were significantly increased (P<0.01),ICAM-I,TNF-α,IL-6,IL-1 were increased (P<0.05)in the group of agedness.(3) The number of leukocytes in the hippocampus decreased significantly in the group of agedness than the groups of young and manhood, especially in the DG and CA3, but there were no significant difference between groups. The leukocytes,astrocytes,synapse and myelinate in the hippocampus were aging in group of agedness.(4) The old rats showed decreased ability of AAR,PAR and spatial resolution(P<0.05).Conclution(1) The histological characters of carotid endotheliocyte in group of youth: The endotheliocyte formed regularly and liquidly with abundant cytoplasm and organelle, the surfaces of subendothelial were smooth. The endotheliocyte's Karyotheca were integrated. There were abundant microvillus On the surface of endotheliocyte. The histological characters of endotheliocyte in group of manhood: The endotheliocyte were integrated but not smooth. The endotheliocyte formed regularly and contained exiguities'cytoplasm and organelles. On the surface of endotheliocyte, there were some red cell, the microvillus were reduced or disappeared. The endotheliocyte's structure were obscure.The histological characters of endotheliocyte in group of agedness: The endotheliocyte lack of regularly and liquidly with rare cytoplasm and organelle, the surfaces of subendothelial were not smooth. The endotheliocyte's Karyotheca were not integrated. There were plenty of microvillus On the surface of endotheliocyte . there are three kinds of character in endotheliocyte: change,apoptosis and dispeared.(2) In group of agedness, the expression of ICAM-I,TNF-α,IL-6,IL-1 and Hs-CRP in blood serum were increased.(3) Degeneration of leukocytes cells could be seen in the group of agedness.(4) Cognitive function declined in old rats.