BACKGROUND AND PURPOSE Subarachnoid hemorrhage frequently leads to long-term cerebral artery narrowing called vasospasm. Very early changes in cerebral arteries have not been studied extensively and may be critical for the later pathological developments. We therefore determined what changes in the reactivity of cerebral arteries could be observed after 10 minutes' or 24 hours' contact with sub...

The most common cause of decerebrate posture is brain damage at the level of the brain stem. However, decerebration could occur without any brain stem damage by occlusion of both carotid arteries (1, 2). A 60-year-old man was admitted to the hospital because of loss of consciousness while working, immediately followed by decerebrate extensor posture. An electrocardiogram showed atrial fibrillat...

BACKGROUND The authors determined the segmental effects of intracarotid verapamil in human subjects by using a novel method of measuring proximal and distal cerebrovascular resistance. Their hypothesis was that intracarotid verapamil, a calcium channel-blocking drug that augments cerebral blood flow and reverses arterial spasm, would decrease both the proximal-conductance and the distal-arterio...

Moyamoya syndrome is an increasingly recognized arteriopathy associated with cerebral ischemia and has been associated with approximately 6% of childhood strokes. It is characterized by chronic progressive stenosis at the apices of the intracranial internal carotid arteries, including the proximal anterior cerebral arteries and middle cerebral arteries and ultimately results in decreased cerebr...

BACKGROUND AND PURPOSE We tested the hypothesis that elevated superoxide production by Nox2-NADPH oxidase occurs in cerebral arteries during hypercholesterolemia and causes decreased nitric oxide function. METHODS Wild-type (WT), apolipoprotein E-deficient (ApoE(-/-)) and Nox2(-/-)/ApoE(-/-) mice were fed a high-fat diet for 7 to 14 weeks. Basal superoxide production by cerebral arteries was ...

At 110-111 days gestation, instrumented fetal sheep were administered saline or dexamethasone (2.2 microgram. kg(-1). h(-1) iv) for 48 h. Measurement of fetal blood pressure showed a greater increase in dexamethasone-treated (n = 6) compared with control (n = 5) fetuses (7.3 +/- 2.3 vs. 0.6 +/- 2.3 mmHg, P < 0.05). Fetuses were delivered by cesarean section, and the femoral muscle and brain wer...

BACKGROUND AND PURPOSE Chronic hypertension decreases internal diameter of cerebral arteries and arterioles. We recently showed that short-term treatment with the angiotensin II receptor blocker telmisartan restored baseline internal diameter of small cerebral arterioles in spontaneously hypertensive rats (SHR), via reversal of structural remodeling and inhibition of the angiotensin II vasocons...

Cerebral blood vessels contain both sympathetic and nitric oxide (NO) synthase (NOS)-containing nerves. NO has been proposed to modulate smooth muscle function and adrenergic nerve activity, and the nature of this modulation is controversial: some data show NO inhibits norepinephrine (NE) release, whereas others suggest that NO augments release. To test the hypothesis that in cerebral arteries ...

We report an attempt to obtain images of the basal cerebral arteries and to measure the quantitative flow velocity in these arteries from outside the skull via the color Doppler imaging method. In 25 healthy volunteers, 22-41 years old, the transducer was positioned just superior to the zygomatic arch and anterior to the external ear canal. The absolute flow velocity was calculated by dividing ...

introduction: the present study evaluated morphological changes of ca1 hippocampal neurons following transient bilateral common carotid and permanent left middle cerebral arteries occlusion, also the neuroprotective effects of aspirin i.p injection was inducing assessed after ischemia in male rat. material and methods: in this experiment, 4 groups of animals were used including; control, sham, ...