Networks of GABAergic neurons are key elements in the generation of gamma oscillations in the brain. Computational studies suggested that the emergence of coherent oscillations requires hyperpolarizing inhibition. Here, we show that GABA(A) receptor-mediated inhibition in mature interneurons of the hippocampal dentate gyrus is shunting rather than hyperpolarizing. Unexpectedly, when shunting in...

The fetal liver is located at the crossroads of the umbilical venous circulation. Anatomically, the ductus venosus (DV) and the intrahepatic branches of the portal vein are arranged in parallel. The actual DV shunting rate, i.e. the percentage of umbilical blood flow entering the DV measured by Doppler velocimetry, seems to be lower than that estimated using radioactively-labeled microspheres. ...

endothelial nitric oxide synthase (enos) produces nitric oxide (no) from l-arginine and is important for the maintenance of cardiovascular homeostasis. congestive heart failure (chf) generally results in increased pulmonary blood flow and if untreated leads to pulmonary hypertension and end stage heart failure. we therefore hypothesized that increased pulmonary flow without changes in pressure ...

This manuscript will focus on a rare complication: shunting through a patent foramen ovale (PFO) as a long term complication of right sided pneumonectomy or bilobectomy. Three patients who were diagnosed with shunting through a patent foramen ovale following lung resection are described. In these patients right ventricular compression by the elevated right hemidiaphragm was the cause of shuntin...

A 74 year old woman had right to left shunting through an atrial septal defect despite normal right heart pressures. Acute volume expansion temporarily reduced the shunt. Contrast echocardiography and angiography demonstrated that this shunting occurred almost exclusively from the inferior vena cava. At surgery a redundant flap of septum secundum was found that was adjacent to the inferior vena...

The aim of this study was to determine whether the improvement of cerebrospinal fluid (CSF) flow dynamics by CSF shunting, can suppress the oligomerization of amyloid β-peptide (Aβ), by measuring the levels of Alzheimer's disease (AD)-related proteins in the CSF before and after lumboperitoneal shunting. Lumbar CSF from 32 patients with idiopathic normal pressure hydrocephalus (iNPH) (samples w...

Shunting Inhibition Manuscript #1405 Shunting Inhibition Does Not Have a Divisive E ect on Firing Rates Gary R. Holt and Christof Koch October 22, 1996 Computation and Neural Systems Program, 139-74 California Institute of Technology, Pasadena, CA 91125, USA. RUNNING HEAD: Shunting Inhibition Correspondence to: Gary Holt Computation and Neural Systems Program 139{74 Caltech Pasadena, CA 91125 T...

AIM To determine the mean carotid artery stump pressure (SP) at which patients develop neurological changes while undergoing awake carotid artery endarterectomy (CEA) under cervical block anaesthesia (CBA). METHODS A prospective analysis was carried out of patients undergoing awake CEA under CBA between February 2004 and April 2007. All patients had mean SP measured, with selective shunting o...

The aim of this study was to evaluate whether possible preglomerular arterial-to-venous oxygen shunting is affected by the interaction between renal preglomerular carbon dioxide and oxygen transport. We hypothesized that a reverse (venous-to-arterial) shunting of carbon dioxide will increase partial pressure of carbon dioxide and decrease pH in the arteries and thereby lead to increased oxygen ...

Portal systemic shunting (PSS) and portal pressure were measured in control rats and in animals with portal hypertension induced by partial portal vein ligation (PPVL). The portal pressure in rats with partial portal vein ligation (13.4 +/- 0.5 mm.Hg.) was significantly higher (p < 0.005) than in the control group (9.6 +/- 0.6 mm.Hg.). Portal systemic shunting measured by consecutive injections...