Background and Purpose-Activators of peroxisome proliferator-activated receptor-␥ (PPAR␥), a member of the PPAR family, increase levels of CuZn-superoxide dismutase (SOD) in cultured endothelium, suggesting a mechanism by which it may exert its protective effect within the brain. These properties raise the question of whether a PPAR␥ agonist may be neuroprotective in models of ischemia without reperfusion, in which oxidative injury is less prevalent. Methods-In 2 groups of rats, 90 minutes of middle cerebral artery (MCA) occlusion was followed by 1 day of reperfusion, with 1 group receiving pioglitazone (a PPAR␥ agonist) starting 72 hours before MCA occlusion (MCAO) and continuing through the day of occlusion, whereas the other group received vehicle only. In 2 comparable groups, the MCA was occluded permanently. One day after occlusion, the animals were tested neurologically and infarct volumes were calculated. In a separate group, rats were treated with pioglitazone or vehicle for 4 days. Tissue was obtained from the cortex and the striatum 2 hours into reperfusion after 90 minutes of MCAO, and the tissue was examined for CuZn-SOD by Western blot. Results-Results show a significant reduction in infarct size in the treated rats, with transient MCAO but not permanent MCAO. There was also an improvement in neurological score in the treated animals after transient MCAO.
Background and objectiveCervicocephalic arterial dissection can cause both ischemic stroke and hemorrhagic stroke. However, spontaneous cervicocephalic arterial dissection presenting only with headache and neck pain has rarely been reported. The clinical features of patients with spontaneous cervicocephalic arterial dissection presenting only with headache and neck pain were investigated.MethodsThe subjects were seven patients with spontaneous cervicocephalic arterial dissection with headache and neck pain alone who were admitted to our hospital during the past 3 years. The clinical features of these patients were investigated. The diagnosis of arterial dissection was based on the criteria of the Strategies Against Stroke Study for Young Adults in Japan.ResultsThe age of the patients (3 males, 4 females) ranged from 35 to 79 (mean, 51.0 ± 16.2) years. Six patients had vertebral artery dissection, one had internal carotid artery dissection, and one had an association of vertebral and internal carotid artery dissection. With the exception of one patient, the headache and neck pain were unilateral. All patients with vertebral artery dissection complained of posterior cervical or occipital pain. In the cases of internal carotid artery dissection, one patient complained of temporal pain, and one patient with co-existing vertebral artery dissection complained of posterior cervical pain. The mode of onset was acute in five patients, thunderclap in one, and gradual and progressive in one. The pain was severe in all cases. Five patients complained of continuous pain, while two had intermittent pain. The quality of the pain was described as throbbing by five patients and constrictive by two. The headache and neck pain persisted for 1 week or longer in six of the seven patients.ConclusionCervicocephalic arterial dissection should be suspected when patients complain of intense unilateral posterior cervical and occipital pain or temporal pain.
Cerebral venous thrombosis presenting as subarachnoid hemorrhage (SAH)
The purpose of this study was to clarify the kinetics of nitric oxide (NO) induced by either endothelial NO synthase (eNOS) or neuronal NO synthase (nNOS) after transient global forebrain ischemia. We investigated NO production and ischemic changes to hippocampal CA1 neurons in eNOS knockout (-/-) mice and nNOS (-/-) mice during cerebral ischemia and reperfusion. NO production was continuously monitored by in vivo microdialysis. Global forebrain ischemia was produced by occlusion of both common carotid arteries for 10 minutes. Levels of nitrite (NO(2)(-)) and nitrate (NO(3)(-)), as NO metabolites, in dialysate were determined using the Griess reaction. Two hours after the start of reperfusion, animals were perfused with 4% paraformaldehyde. Hippocampal CA1 neurons were divided into three phases (severely ischemic, moderately ischemic, surviving), and the ratio of surviving neurons to degenerated neurons was calculated as the survival rate. The relative cerebral blood flow (rCBF) was significantly higher in nNOS (-/-) mice than in control mice after reperfusion. Levels of NO(3)(-) were significantly lower in eNOS (-/-) mice and nNOS (-/-) mice than in control mice during ischemia and reperfusion. NO(3)(-) levels were significantly lower in nNOS (-/-) mice than in eNOS (-/-) mice after the start of reperfusion. Survival rate tended to be higher in nNOS (-/-) mice than in control mice, but not significantly. These in vivo data suggest that NO production in the striatum after reperfusion is closely related to activities of both nNOS and eNOS, and is mainly related to nNOS following reperfusion.
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