Neuroprotective mechanisms of erythropoietin in a rat stroke model.

Objective: This study was designed to investigate the indirect neuroprotective properties of recombinant human erythropoietin (rhEPO) pretreatment in a rat model of transient middle cerebral artery occlusion (MCAO).

Methods: One hundred and ten male Wistar rats were randomly assigned to four groups receiving either 5,000 IU/kg rhEPO intravenously or saline 15 minutes prior to MCAO and bilateral craniectomy or sham craniectomy. Bilateral craniectomy aimed at elimination of the space-consuming effect of postischemic edema.

Combined contrast-enhanced ultrasound and rt-PA treatment is safe and improves impaired microcirculation after reperfusion of middle cerebral artery occlusion.

In monitoring of recanalization and in sonothrombolysis, contrast-enhanced ultrasound (CEUS) is applied in extended time protocols. As extended use may increase the probability of unwanted effects, careful safety evaluation is required. We investigated the safety profile and beneficial effects of CEUS in a reperfusion model.

A rat model for cerebral air microembolisation.

Subtle cerebral air microembolisation (CAM) is a typical complication of various medical interventions such as open heart surgery or angiography and can cause transient or permanent neurological and neuropsychological deficits. Evaluation of the underlying pathophysiology requires animal models that allow embolisation of air bubbles of defined diameter and number. Herein we present a method for the production of gas bubbles of defined diameter and their injection into the carotid artery of rats.

Intravenous immunoglobulin reduces infarct volume but not edema formation in acute stroke.

Objectives: Intravenous immunoglobulin (IVIG) is used for treatment of immunodeficiencies and autoimmune disorders. Recently, IVIG has also been shown to reduce infarct size in acute stroke. Since edema treatment can provide secondary neuroprotective effects, we conducted the present study to evaluate whether edema reduction is the underlying cause of the neuroprotective properties of IVIG in experimental stroke.

Edema formation in the hyperacute phase of ischemic stroke. Laboratory investigation.

Object: Brain edema formation is a serious complication of ischemic stroke and can lead to mechanical compression of adjacent brain structures, cerebral herniation, and death. Furthermore, the space-occupying effect of edema impairs regional cerebral blood flow (rCBF), which is particularly important in the penumbra phase of stroke. In the present study, the authors evaluated the natural course of edema formation in the hyperacute phase of focal cerebral ischemia.

RNase therapy assessed by magnetic resonance imaging reduces cerebral edema and infarction size in acute stroke.

Ischemic stroke causes cell necrosis with the exposure of extracellular ribonucleic acid (RNA) and other intracellular material. As shown recently, extracellular RNA impaired the blood-brain-barrier and contributed to vasogenic edema-formation. Application of ribonuclease 1 (RNase 1) diminished edema-formation and also reduced lesion volume in experimental stroke.

Detrimental effects of 60 kHz sonothrombolysis in rats with middle cerebral artery occlusion.

Recent studies have raised concerns about the safety of low frequency ultrasound in transcranial therapeutic application in cerebral ischemia. This study was designed to evaluate safety aspects and potential deleterious effects of low frequency, 60 kHz ultrasound in treatment of experimental middle cerebral artery occlusion (MCAO) in rats. Forty-five male Wistar rats were submitted to either temporary (90 min; groups I and II) or permanent MCAO (groups III and IV) using the suture technique.

Aggravation of infarct formation by brain swelling in a large territorial stroke: a target for neuroprotection?

Object: In territorial stroke vasogenic edema formation leads to elevated intracranial pressure (ICP) and can cause herniation and death. Brain swelling further impairs collateral blood flow to the ischemic penumbra and causes mechanical damage to adjacent brain structures. In the present study the authors sought to quantify the impact of this space-occupying effect on ischemic lesion formation.