The present study examined the factors responsible for triggering renal hemodynamic adjustments during acute volume expansion. The renal hemodynamic effects of graded volume expansion with 0.9% saline (Sal; 1, 2, and 4% of body wt), 7% BSA solution (0.35, 0.70, and 1.4% body wt), or whole blood from a donor rat (WBL; 0.35, 0.70, and 1.4% body wt) were compared in rats anesthetized with pentobar...

Functional MRI (fMRI) with blood-oxygen level dependency (BOLD) contrast [1, 2] measures the hemodynamic response secondary to neural activity [3]. Typically fMRI uses the echo-planar imaging (EPI) [4] to acquire images covering the whole brain with a TR of a few seconds. Using the magnetic resonance inverse image (InI) technique, the scan time per brain volume can be reduced to 100 ms [5]. To ...

Granger causality is a method for identifying directed functional connectivity based on time series analysis of precedence and predictability. The method has been applied widely in neuroscience, however its application to functional MRI data has been particularly controversial, largely because of the suspicion that Granger causal inferences might be easily confounded by inter-regional differenc...

Objective: Vascular remodeling is an adaptive response to variations in the hemodynamic environment acting on the arterial wall. Remodeling translates into changes of structure, geometry and mechanical properties of the artery. Our aim was to study the remodeling response of pig right common carotid arteries in vitro. Methods: In vivo right carotid arteries are exposed to a non-uniform hemodyna...

treatment of cardiovascular disorders, such as angina pectoris and hypertension. The therapeutic effectiveness of the blockers in these disease states is based on a range of hemodynamic actions, including effects on blood vessels, hearts, and kidneys. Calcium channel blockers are classified into the following three groups on the basis of chemical structures, which show different pharmacological...

A semi-parametric model for estimating hemodynamic response function (HRF) from multi-subject fMRI data is introduced within the context of the General Linear Model. The new model assumes that the HRFs for a fixed brain voxel under a given stimulus share the same unknown functional form across subjects, but differ in height, time to peak, and width. A nonparametric spline-smoothing method is de...

Angiotensin II (Ang II) and atrial natriuretic factor (ANF) appear to act as functional antagonists in the regulation of fluid and electrolyte homeostasis and blood pressure. To further define the relations between these hormones in vivo, we investigated the effect of low doses ofAng II (1-10 ng/kg/min) on plasma ANF levels. We also evaluated the influence ofANF release on the renal and hormona...

BACKGROUND Hemodynamic tandem intracranial lesions (TILs) on intracranial magnetic resonance angiography, which develop flow dependently, have been overlooked clinically in patients undergoing carotid endarterectomy. As they represent severe baseline hemodynamic compromise at the segment, they may be associated with distinctive clinical outcomes. METHODS AND RESULTS We assessed 304 consecutiv...

In perioperative medicine, hemodynamic management aims at an optimization of perfusion pressure and oxygen delivery in order to maintain or restore adequate cellular metabolism (1). To optimize cardiopulmonary function, hemodynamic management triggers the administration of fluids and vasoactive agents according to predefined target values of hemodynamic variables. This is often referred to as “...

BACKGROUND AND PURPOSE Studies have shown that the occurrence of brain aneurysms and risk of rupture vary between locations. However, the reason that aneurysms at different branches of the cerebral arteries have different clinical presentations is not clear. Because research has indicated that aneurysm hemodynamics may be one of the important factors related to aneurysm growth and rupture, our ...