This review summarizes evidence in humans for an association between hyperventilation (HV)-induced hypocapnia and a reduction in cerebral perfusion leading to syncope defined as transient loss of consciousness (TLOC). The cerebral vasculature is sensitive to changes in both the arterial carbon dioxide (PaCO2) and oxygen (PaO2) partial pressures so that hypercapnia/hypoxia increases and hypocapn...

BACKGROUND Fructus mume (F. mume) has been used as a traditional medicine for many years in Asian countries. The present study was designed to determine the effect of a 70% ethanol extract of F. mume on white matter and hippocampal damage induced by chronic cerebral hypoperfusion. METHODS Permanent bilateral common carotid artery occlusion (BCCAo) was performed on male Wistar rats to induce c...

Reperfusion into focal ischemia was studied in 25 cats after middle cerebral artery (mca) occlusion of 15 min to 2 hours duration. Changes in cerebral blood flow (CBF) were followed with the hydrogen clearance method in the center and periphery of the ischemic lesion expected. Postischemic hyperperfusion was found often after 15 and 30 min ischemia and regularly after 60 min mca occlusion. It w...

We used single-photon emission computed tomography with technetium-99m hexamethylpropylene amine oxime in 18 studies on 13 patients with subarachnoid hemorrhage to determine whether any changes in cerebral blood flow could be correlated with clinical or computed tomographic evidence of delayed ischemia. Among the seven patients without focal neurologic deficits, regional cerebral hypoperfusion ...

Early changes in systemic vascular stiffness and endothelial function can contribute to altered cerebrovascular hemodynamics impaired cognitive function; additionally, these point potential targets for prevention treatment strategies people with mild impairment. Although the pathogenic mechanisms underlying are heterogeneous complex, one common feature is development of cerebral blood flow (CBF...

A multiple analysis of the cerebral oxidative stress was performed on a physiological model of dementia accomplished by three-vessel occlusion in aged rats. The forward rate constant of creatine kinase, k(for), was studied by saturation transfer (31)P magnetic resonance spectroscopy in adult and aged rat brain during chronic hypoperfusion. In addition, free radicals in aging rat brain homogenat...

BACKGROUND AND PURPOSE An animal model has been developed to elucidate the pathological changes in brain cytoskeletal proteins during chronic hypoperfusion. METHODS Newly designed coiled clips were placed around both carotid arteries of Mongolian gerbils (n = 10) to cause stenosis without occlusion. Those gerbils showing impaired learning ability by the passive avoidance paradigm were killed ...

BACKGROUND AND PURPOSE Silent information regulator 2 homolog 1 (SIRT1) is a protein deacetylase that has been reported to suppress neurodegenerative and cardiovascular diseases in model organisms. We hypothesized that neurovascular protection is one of the diverse actions of SIRT1. This study was designed to determine whether SIRT1 protects against the consequences of cerebral hypoperfusion in...