Chronic hypertension is associated with a lower cerebral vascular reserve due to thickening of the media of cerebral vessels. The goal of the present study was to determine if long-term inhibition of angiotensin converting enzyme with cilazapril, a new long-acting angiotensin converting enzyme inhibitor, could improve cerebral vascular reserve. For this purpose, two groups of 12 spontaneously h...

BACKGROUND AND PURPOSE We determined the effects of inhibiting the production of cerebral endothelium-derived nitric oxide on pial artery diameter, cortical blood flow, and vascular morphology. METHODS An inhibitor of endothelium-derived nitric oxide synthesis, NG-nitro-L-arginine methyl ester hydrochloride (L-NAME), or an equivalent volume of 0.9% saline was infused into rats intra-arteriall...

The effect of local hypercapnic acidosis or local hypocapnic alkalosis on pial arterioles were studied in anesthetized cats equipped with a cranial window for the direct observation of the pial microcirculation of the parietal cortex. Changes in PCO2 and pH of the extracellular fluid were induced by perfusing the space under the cranial window with artificial cerebrospinal fluid equilibrated wi...

Tuberculum sellae meningiomas frequently produce visual loss by direct compression from tumor, constriction of the optic nerve (ON) under the falciform ligament, and/or ON ischemia. The authors hypothesized that changes in visual function after tumor removal may be related to changes in blood supply to the ON that might be seen in the pial circulation at surgery. Indocyanine green (ICG) angiogr...

Previous studies have shown that the pial microcirculation remodeling improves neurological outcome after middle cerebral artery occlusion (MCAO), accompanied by higher expression of vascular endothelial growth factor (VEGF) and endothelial nitric oxide synthase (eNOS), modulating in vivo angiogenesis. This study was aimed to assess the effects of bone marrow mesenchymal stem cells (BM-MSCs) in...

Moyamoya disease (MMD) is a cerebrovascular occlusive disorder which causes recurrent strokes and transient ischemic attacks in children. The arteriopathy of MMD targets the internal carotid arteries (ICA) and their branches resulting in ischemia of the ICA circulation. Small perforator branches of the ICA dilate to provide collateral perfusion to ischemic areas. This small vessel dilatation cr...

A non-traumatic approach to the subarachnoid space near the circle of Willis is demonstrated in this study. The approach is made between the olfactory bulb and frontal lobe. Following perfusion with Evans blue dye no leakage was observed into the parenchyma indicating no tissue damage had occurred. No gross bleeding or cerebral vasospasm was visible in the middle meningeal artery (dural), the s...

BACKGROUND Pial arteriolar responses to flow contribute to regulation of cerebral perfusion and vary according to the transmural pressure to which the vessel is exposed. This study determined the effect of increased glucose concentration on the flow responses of pial arterioles at low and high levels of transmural pressure. METHODS Pial arterioles from Sprague-Dawley rats were mounted in a pe...

The relationships among cerebral blood flow, cerebral blood volume, intracranial pressure (ICP), and the action of cerebrovascular regulatory mechanisms (autoregulation and CO2 reactivity) were investigated by means of a mathematical model. The model incorporates the cerebrospinal fluid (CSF) circulation, the intracranial pressure-volume relationship, and cerebral hemodynamics. The latter is ba...

BACKGROUND Propofol and sevoflurane are commonly used anesthetics for neurosurgery. The aim of the study was to compare the effects of propofol with sevoflurane on cerebral pial arteriolar and venular diameters during global brain ischemia and reperfusion. METHODS Japanese white rabbits were anesthetized with propofol (n=11), sevoflurane (n=9), or the combination of sevoflurane and intralipid...