BACKGROUND It is difficult to non-invasively visualize changes in regional cerebral blood flow caused by manual compression of the carotid artery. PURPOSE To visualize dynamic changes in regional cerebral blood flow during and after manual compression of the carotid artery. MATERIAL AND METHODS Two healthy volunteers were recruited. Anatomic features and flow directions in the circle of Wil...

Smoking is a major health hazard with proven deleterious effects on the cerebral circulation, including a decrease in cerebral blood flow and a high risk for stroke. To elucidate cellular mechanisms for the vasoconstrictive and pathological effects of nicotine, we used a nystatin-perforated patch-clamp technique to study Ca(2+) channels and Ca(2+)-activated K(+) (BK) channels in smooth muscle c...

In murine neurocysticercosis (NCC), caused by infection with the parasite Mesocestoides corti, the breakdown of the Blood Brain Barrier (BBB) and associated leukocyte infiltration into the CNS is dependent on the anatomical location and type of vascular bed. Prior studies of NCC show that the BBB comprised of pial vessels are most affected in comparison to the BBB associated with the vasculatur...

To study the effect of histamine (HA) on brain blood flow and capillary permeability, bilateral parietal craniectomies were made in cats anesthetized with nitrous oxide and ketamine. The dura was removed and solutions of HA in mock cerebrospinal fluid (CSF) in varying concentrations ranging from 10(-5) M to 10(-1) M were irrigated continuously onto the exposed brain while local cerebral blood f...

In patients with high-grade atherosclerotic stenosis or occlusion of the extracranial cerebral arteries, subarachnoid hemorrhage (SAH) may occur, potentially due to rupture of fragile dilated pial collateral vessels. This association has been well described in Moyamoya disease. There are only few cases in the literature that reported SAH due to bilateral carotid artery stenosis but intraventric...

A 44 year old male patient, non smoker, hypertensive was admitted with loss of consciousness followed by transient weakness of the right side of the body. He gave a past history of recurrent TIAs. On admission, he was fully conscious and oriented. Pulse 60/mt, BP 120/80 mm Hg. There were no cutaneous telangiectasias. There was no carotid bruit. CVS S1 S2 heard normally. Central nervous system e...

Smoking is a major health hazard with proven deleterious effects on the cerebral circulation, including a decrease in cerebral blood flow and a high risk for stroke. To elucidate cellular mechanisms for the vasoconstrictive and pathological effects of nicotine, we used a nystatin-perforated patch-clamp technique to study Ca channels and Ca-activated K (BK) channels in smooth muscle cells isolat...

A former model of cerebrovascular regulation and intracranial pressure dynamics has been improved to account for the effect of oxygen lack on cerebral vessels and cerebral blood flow (CBF). Model assumes that CBF regulation is the result of three distinct feedback mechanisms working on pial arteries and arterioles: they represent CO2 reactivity, tissue hypoxia, and a mechanism (either pressure-...

Background: The mechanisms underlying cerebral hypercapnic vasodilatation are not fully understood. Objective: To investigate the role of nitric oxide (NO) and ATP-sensitive potassium (KATP) channels in basal blood flow regulation and hypercapnia-induced vasodilatation in rabbit cerebral blood vessels. Methods: The change in cerebral blood flow was measured by a laser Doppler flowmeter in 18 Ne...