0000000000188392
AUTHOR
Irina Lasarzik
showing 7 related works from this author
Statistical analysis of latency outcomes in behavioral experiments
2011
In experimental designs of animal models, memory is often assessed by the time for a performance measure to occur (latency). Depending on the cognitive test, this may be the time it takes an animal to escape to a hidden platform (water maze), an escape tunnel (Barnes maze) or to enter a dark component (passive avoidance test). Latency outcomes are usually statistically analyzed using ANOVAs. Besides strong distributional assumptions, ANOVA cannot properly deal with animals not showing the performance measure within the trial time, potentially causing biased and misleading results. We propose an alternative approach for statistical analyses of latency outcomes. These analyses have less distr…
Effect of autologous blood transfusion on cerebral cytokine expression.
2011
BACKGROUND: Autologous blood transfusion (ABT), for example, by means of cell saver equipment, is used to reduce the need for allogenic blood transfusion in patients with high perioperative blood loss. This study investigated the effect of blood/extracorporal surface interaction during withdrawal and retransfusion of shed autologous blood on cerebral inflammation in rats. Rats subjected to hypotension with cerebral ischemia served as positive controls. METHODS: Eighty-eight male Sprague-Dawley rats were anesthetized with sevoflurane, instrumented, and randomly assigned to the following groups: sham-operation (SHAM), autologous blood withdrawal/transfusion only (ABT), or bilateral carotid ar…
High dose infusion of activated protein C (rhAPC) fails to improve neuronal damage and cognitive deficit after global cerebral ischemia in rats
2013
Abstract Purpose : Recent studies demonstrated anticoagulatory, antiinflammatory, antiapoptotic, and neuroprotective properties of activated protein C (APC) in rodent models of acute neurodegenerative diseases, suggesting APC as promising broad acting therapeutic agent. Unfortunately, continuous infusion of recombinant human APC (rhAPC) failed to improve brain damage following cardiac arrest in rats. The present study was designed to investigate the neuroprotective effect after global cerebral ischemia (GI) with an optimized infusion protocol. Methods : Rats were subjected to bilateral clip occlusion of the common carotid arteries (BCAO) and controlled hemorrhagic hypotension to 40 mmHg for…
Dose-dependent effect of S(+) ketamine on post-ischemic endogenous neurogenesis in rats.
2009
Background: Ketamine is a non-competitive antagonist at N-methyl-d-aspartate (NMDA) receptors and reduces neuronal injury after cerebral ischemia by blocking the excitotoxic effects of glutamate. However, cerebral regeneration by means of endogenous neurogenesis may be impaired with blockade of NMDA receptors. The effects of S(+) ketamine on post-ischemic neurogenesis are unknown and investigated in this study. Methods: Thirty-two male Sprague–Dawley rats were randomly assigned to the following treatment groups with intravenous S(+) ketamine anesthesia: S(+) ketamine 0.75 mg/kg/min with or without cerebral ischemia and S(+) ketamine 1.0 mg/kg/min with or without cerebral ischemia. Eight non…
Assessment of postischemic neurogenesis in rats with cerebral ischemia and propofol anesthesia.
2009
Background Postischemic endogenous neurogenesis can be dose-dependently modulated by volatile anesthetics. The intravenous anesthetic propofol is used during operations with a risk of cerebral ischemia, such as neurosurgery, cardiac surgery, and vascular surgery. The effects of propofol on neurogenesis are unknown and, therefore, the object of this study. Methods Eighty male Sprague-Dawley rats were randomly assigned to treatment groups with propofol administration for 3 h: 36 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia and 72 mg x kg(-1) x h(-1) propofol with or without cerebral ischemia. In addition, 7 rats with propofol administration for 6 h and 14 treatment-naive ra…
Mouse photoreceptor synaptic ribbons lose and regain material in response to illumination changes
2004
Abstract Chemical synapses equipped with ribbons are tonically active, high-output synapses. The ribbons may play a role in the trafficking of synaptic vesicles. Recent findings in retinal rod cells of BALB/c mice indicate that ribbons are large and smooth in the dark phase, and, due to the formation and release of protrusions, small during the light phase. As a consequence of these changes, ribbons may traffick fewer vesicles in the light than in the dark phases. The aim of the present study was to find out whether the above ribbon changes in this mouse strain are strictly illumination-dependent and which signalling processes may be involved. Here, we show that ribbons form protrusions and…
Mild Hypothermia Has No Long-Term Impact on Postischemic Neurogenesis in Rats
2009
Postischemic improvement of functional outcome by therapeutic hypothermia may be related to cerebral regeneration by postischemic neurogenesis. We investigated whether mild peri-ischemic hypothermia leads to a long-term increase in postischemic neurogenesis.Seventy male sevoflurane-anesthetized Sprague Dawley rats were randomly assigned to the following treatment groups: normothermic ischemia, intraischemic hypothermia, and postischemic hypothermia with corresponding sham-operated controls. Fifteen naïve rats were investigated as reference for natural neurogenesis. Forebrain ischemia was induced by bilateral common carotid artery occlusion and hemorrhagic hypotension. In normothermic groups…