The aim of the present study was to investigate the effect of a short-term (3-day) simulated microgravity with and without daily dorsoventral gravitation (-G(x)) for 1 h on myogenic tone and vasoconstrictor responsiveness of the middle cerebral artery and mesenteric third-order small artery in rats. The tail-suspension (SUS) model was used to simulate cardiovascular deconditioning due to microgravity. Daily restoring to normal standing (STD) posture for 1 h was adopted to provide -G(x) as the countermeasure. Segments of middle cerebral artery and mesenteric third-order small artery were isolated and cannulated. Vascular diameters in response to increased intraluminal pressure (from 20 mmHg to 120 mmHg, by 20 mmHg steps) of isolated arteries under no-flow conditions were recorded by a Pressure Myograph System in both physiologic salt solution (PSS) (active diameter, Da) and calcium-free PSS (passive diameter, Dp). The myogenic tone was calculated by (Dp-Da)/Dpx100%. Vasoconstrictor responsiveness of the isolated middle cerebral artery to serotonin and that of small mesenteric artery to phenylephrine were assessed in the PSS under an intraluminal pressure of 40 mmHg. The results showed that SUS induced an enhancement of the myogenic tone and vasoconstrictor responsiveness in the isolated middle cerebral artery but a depression of those in the small mesenteric artery. Daily STD for 1 h prevented the depression of myogenic tone and vasoconstrictor responsiveness in the small mesenteric artery, but did not prevent the functional enhancement in the middle cerebral artery. These data suggest that a short-term simulated microgravity may result in different alterations in the function of the cerebral artery and the resistance vessel in the hind-body. Moreover, only the decrease of function in these resistance vessels, not in the cerebral arteries, can be prevented by such a countermeasure of daily STD for 1 h.
Animals ; Cerebral Arteries ; pathology ; Hindlimb Suspension ; Mesenteric Arteries ; pathology ; Pressure ; Rats ; Serotonin ; pharmacology ; Vascular Resistance ; Vasoconstriction ; Weightlessness Simulation

Central nervous system is often involved by herpes zoster but it is very rarely seen that contralateral hemiparesis or hemiplegia developed after herpes zoster ophthalmicus. We report a case of herpes zoster ophthalmicus followed by the delayed contralateral hemiparesis. A 33-year-old man developed acute cerebral infarction and resultant right hemiparesis 44 days after herpes zoster ophthalmicus in the left side. Brain CT disclosed hypodense area in the left basal ganglia. Cerebral angiography revealed segmental narrowing of M1 portion of the right middle cerebral artery.
Adult ; Cerebral Angiography ; Cerebral Arteries/pathology ; Cerebral Infarction/*etiology/radiography ; Dominance, Cerebral ; Hemiplegia/*etiology ; Herpes Zoster Ophthalmicus/*complications ; Humans ; Male ; Tomography, X-Ray Computed ; Vasculitis/etiology

BACKGROUND: The aim of this study is to evaluation of lower extremity with doppler ultrasonography in the thrombotic poststroke patients. METHOD: The subjects were 24 thrombotic poststroke patients. We analyzed the stenosis or obstruction in the lower extremity artery with a doppler ultrasound and the cerebral artery with a magnetic resonance angiography. RESULTS: In the lower extremity artery, 3 patients had the complete obstruction in one and more vessels, 7 patients had the luminal narrowing more than 50% in one and more vessels, 11 patients had the luminal narrowing less than 50% in one and more vessels. And in the cerebral artery, 9 patients had the Obstruction or stenosis of the artery without diffuse atherosclerosis, 15 patients had the arterial obstruction or stenosis with diffuse atherosclerosis, or multiple arterial pathology. CONCLUSION: In this study, poststroke patients with arterial obstruction or stenosis with diffuse atherosclerosis in the cerebral artery had more severe atherosclerotic change in the lower extremity(p<0.05). We recommended to the evaluation of a doppler ultrasound of lower extremity in the thrombotic poststroke patients with diffuse atherosclerotic change of the cerebral artery.
Arteries ; Atherosclerosis ; Cerebral Arteries ; Constriction, Pathologic ; Humans ; Lower Extremity* ; Magnetic Resonance Angiography ; Pathology ; Phenobarbital ; Stroke ; Ultrasonography ; Ultrasonography, Doppler*

Adult ; Carotid Artery Diseases ; pathology ; Carotid Artery, Internal ; pathology ; Cerebral Arteries ; abnormalities ; Humans ; Magnetic Resonance Imaging ; Male

OBJECTIVETo investigate the role of hypertension in the pathogenesis of cerebral aneurysms in rats.

METHODSTwenty spontaneous hypertensive rats (SHR) and 10 Wistar-Kyoto rats (WKY) were included in this observational study. Animals were fed with normal diet and drinking water. No experimental modifications were undertaken in either group. They were sacrificed at one year of age, the bifurcations of the circle of Willis were dissected and longitudinal serial sections were prepared for light microscopic and transmission electron microscopic study.

RESULTSIn the SHR group, 2 of the 20 rats formed an aneurysm respectively at the bifurcations of the basilar artery. As revealed by electron microscopy, injury at the bifurcation of the artery first occurred on the steeper side of the intimal pad. Furthermore, loss of endothelial cells, small depressions on the intima, disruptive internal elastic lamina and lymphocytes or red blood cells infiltration were noted at the steeper side of the intimal pad. No significant changes were observed in WKY group.

CONCLUSIONSCerebral aneurysms can form spontaneously in SHR without ligation of the common carotid artery and without a diet containing beta-aminoproprionitrile. Long-standing systemic arterial hypertension is one of the etiological factors that contributes to aneurysm formation in SHR rats.

Animals ; Cerebral Arteries ; pathology ; Hypertension ; complications ; Intracranial Aneurysm ; etiology ; pathology ; Male ; Rats ; Rats, Inbred SHR ; Rats, Inbred WKY

BACKGROUND: The pulsatility index (PI) measured by a transcranial Doppler (TCD) has been postulated to reflect the vascular resistance that is distal to the artery being examined. Therefore, pathologies of small perforating arteries may affect the PI of the proximal artery. Microangiopathy is a common vascular complication of diabetes mellitus (DM), which may contribute to the development of small infarctions involving the perforating artery, and may be reflected on the PI. METHODS: We enrolled patients with acute cerebral infarctions who were examined by TCD, MRI, and MRA and fulfilled the following criteria: 1)an infarction of less than 2 cm size involving a single perforating arterial territory; 2)no significant arterial stenosis on MRA; and 3)no cardioembolic sources. Patients were divided into either a group with DM, or without and TCD findings were compared. RESULTS: The DM group showed higher PI than non-DM (0.99 v.s. 0.85 for the right middle cerebral artery; 1.02 v.s. 0.85 for the left middle cerebral artery; and 0.94 v.s. 0.78 for the basilar artery). The mean flow velocity was comparable between the groups. Multivariate linear regression analysis revealed that the duration of DM was a significant predictor of elevated PI of the bilateral MCA and basilar artery and that age was another significant predictor in the case of basilar artery. CONCLUSIONS: The elevated PIs in DM patients suggest the possible role of diabetic microvascular complications in the development of the lacunar infarction. The PI measurement using TCD may be a useful marker of the lacunar infarction, especially in DM patients.
Arteries ; Basilar Artery ; Cerebral Infarction ; Constriction, Pathologic ; Diabetes Mellitus ; Humans ; Infarction ; Linear Models ; Magnetic Resonance Imaging ; Middle Cerebral Artery ; Pathology ; Stroke, Lacunar* ; Vascular Resistance

BACKGROUND: Several western studies have found an occurrence of abnormal angiographic findings in 60-80% of patients with carotid artery territory transient ischemic attack(below carotid TIA) and showed that the location of pathology was frequent in extracranial portion of carotid artery. No accurate studies have been accomplished in our country and some racial differences may exist. So we studied the angiographic findings in patients with carotid TIA. METHODS: Thirty two patients with carotid TIA were included, but patients with non-atherosclerotic origin were excluded. MRI and MRA were checked simultaneously in all patients within 7 days after the last TIA. We evaluated the location, type and degree of the angiographic abnormalities and defined clinical factors related to the presence of vascular lesions. The criteria of significant abnormal findings were stenosis of more than 50%, ulceration or irregularity of carotid territory arteries contralateral to clinical symptoms. RESULTS: Thirteen(40.6%) patients showed significant angiographic abnormalities related with the symptoms of TIA, and M1 portion of middle cerebral artery was the most frequent site, in 7 of 13 patients(53%). Patients with TIAs lasted less than 30 min.(P=0.011) and with TIAs occurred more than 4 times a day(P=0.029), had more frequent angiographic abnormalities. But there were no significant differences according to the presence of related acute cerebral infarction, gender and risk factors of stroke. CONCLUSIONS: In our study, the prevalence of angiographic abnormality and the location of vascular lesion were concordant with the Japanese studies but quite different with the western studies, and we suggest that this may be due to differences in dietary life and race.
Angiography* ; Arteries ; Asian Continental Ancestry Group ; Carotid Arteries ; Cerebral Infarction ; Constriction, Pathologic ; Continental Population Groups ; Humans ; Ischemic Attack, Transient* ; Magnetic Resonance Imaging ; Middle Cerebral Artery ; Pathology ; Prevalence ; Risk Factors ; Stroke ; Ulcer

After the spontaneous relief of initial symptoms by traumatic carotid-cavernous fistula (CCF), paradoxical worsening of patient's condition can be followed. We present a case of a 60-yr-old man whose audible bruit from a traumatic CCF had completely disappeared. A few days later, however, the patient had spontaneous intracerebral hematoma with cortical venous drainage. Complete obliteration of the fistula was achieved after embolization. When initial audible bruit in traumatic CCF disappears suddenly, cerebral angiography should be performed to differentiate venous hypertension by the hemodynamic changes of the cavernous sinus channels from spontaneous resolution of CCF.
Brain/pathology ; Carotid Arteries/pathology ; Carotid-Cavernous Sinus Fistula/*complications/*pathology/therapy ; Cerebral Angiography/methods ; Cerebral Hemorrhage, Traumatic/*etiology/therapy ; Humans ; Male ; Middle Aged ; Research Support, Non-U.S. Gov't ; Tomography, X-Ray Computed/methods

OBJECTIVEHuman cytomegalovirus (HCMV), especially the immediate early (IE) gene of the virus, has been implicated in the pathogenesis of atherosclerosis. The aim of this study was to confirm the presence of HCMV IE gene DNA in intracranial artery walls and the association of the virus with the development of atherosclerosis.

METHODSHCMV IE gene was tested in formaldehyde-fixed intracranial arteries from 35 cases with cerebral atherosclerosis and 20 negative controls. In situ hybridization as well as polymerase chain reaction (PCR) was used to detect the presence of DNA in sections of paraffin-embedded tissue samples. Probes and primers were derived from major immediate early (MIE) genomic regions of cytomegalovirus strain AD169.

RESULTSThe DNA of HCMV was found in 40.0% and 10.0% of arterial walls with atherosclerosis and negative control group by in situ hybridization, respectively, in 60.0% and 30.0% by PCR, respectively. Significant deference was found between them (P=0.018, P=0.032). There was also significant difference between grade III-IV and grade I-II atherosclerosis by both methods (P=0.027, P=0.009).

CONCLUSIONThe results suggested that HCMV IE DNA exists in the atherosclerotic arterial walls, therefore, there might be an association between the IE gene in intracranial artery walls and the atherosclerosis. The arterial wall with the smooth muscle cells, might be the potential site of the virus persistence. HCMV may play a role in the pathogenesis of the atherosclerosis.

Aged ; Carotid Arteries ; pathology ; virology ; Cerebral Arteries ; pathology ; virology ; Cytomegalovirus ; genetics ; pathogenicity ; Cytomegalovirus Infections ; DNA, Viral ; analysis ; Female ; Gene Expression ; Genes, Immediate-Early ; Humans ; In Situ Hybridization ; Intracranial Arteriosclerosis ; etiology ; pathology ; virology ; Male ; Polymerase Chain Reaction

OBJECTIVEA new rat model of cerebral infarction was developed to elucidate the contribution of vascular endothelial cell during focal cerebral infarction formation.

METHODSForty-eight Sprague-Dawley (SD) rats were randomly divided into the model group, sham operation group, and control group for indexes observation of triphenyltetrazolium chloride (TTC) dyeing, neurological deficit, plasma tissue-type plasminogen activator (tPA) activity, plasminogen activator inhibitor (PAI) activity, thromboxane B(2) (TXB(2)) content, and 6-keto-prostaglandin (6-keto-PGF(1alpha)) content.

RESULTS(1) The highest neurological score appeared at 6 h after operation, descending significantly at sequential time. (2) Using TTC dyeing and optical microscope technique, pathological changes in brains were observed. (3) Compared with control group and sham operation groups, there was a decrease in tPA activity of model rats at the initial 12 h after injection of sodium laurate (P < 0.05), PAI activity decreased markedly in the model group at 24 h after injection of sodium laurate. (4) In plasma TXB(2) concentration reached the highest level compared at 6 h after injection of sodium laurate, but there were not obvious differences in plasma 6-keto-PGF(1alpha) concentration among all groups (P > 0.05).

CONCLUSIONFocal cerebral infarction in rats could be induced by some sodium laurate, showing ischemic cerebrum necrosis, function disorder of vascular endothelium-platelet, fibrinolysis abnormality. This model could play an important role in researching the contribution of vascular endothelial cell during cerebral infarction development, preventing and curing by traditional Chinese medicine.

Animals ; Carotid Arteries ; Cerebral Infarction ; chemically induced ; pathology ; physiopathology ; Disease Models, Animal ; Endothelial Cells ; pathology ; Lauric Acids ; administration & dosage ; Ligation ; Rats ; Rats, Sprague-Dawley