Alexandra Kretz

Learn More
1. Most segments of the gastrointestinal tract secrete HCO3-, but the molecular nature of the secretory mechanisms has not been identified. We had previously speculated that the regulator for intestinal electrogenic HCO3- secretion is the cystic fibrosis transmembrane regulator (CFTR) channel. To prove this hypothesis, we have now measured HCO3- secretion(More)
The cytokine hormone erythropoietin (EPO) has proved neuroprotective in CNS injury, and clinical trials for ischemic stroke are ongoing. The capability of EPO to restore postmitotic CNS architecture and function by fibre regeneration has not been examined. Here, we compared in vitro outgrowth capacity of adult retinal ganglion cells (RGCs) following optic(More)
The retina is an easily accessible part of the CNS with a well-defined cytological architecture. It allows for detailed study of the regulation of neurogenesis, determinants of cell fate specification, and signals for cell survival versus programmed cellular death during development. Within the retina, retinal ganglion cells (RGCs) are the only neurons(More)
BACKGROUND & AIMS Duodenal bicarbonate secretion is in part mediated by an apical Cl-/HCO3- exchanger of unknown molecular nature. The recently discovered dra (down-regulated in adenoma) gene encodes a transport protein (DRA) for SO4(2-), Cl-, and HCO3-. The aim of this study was to investigate whether DRA may be the duodenal apical Cl-/HCO3- exchanger. (More)
Heat shock proteins (Hsps) are stress proteins that mediate protein stabilization in various tissues and protect cells from environmental stress. Novel evidence suggests that overexpression of the small heat shock protein 27 (Hsp27) in neurons protects against neurotoxic stimuli and may act as an inhibitor of neurodegeneration. Overexpression of Hsps has(More)
Macrophages are thought to represent a first line of defense in anti-tumor immunity. Despite infiltration by microglial cells, however, malignant gliomas are still highly aggressive tumors. We here identify monocyte chemoattractant protein-1 (MCP-1) as a critical chemoattractant for glioma-infiltrating microglial cells. MCP-1-transfected rat CNS-1 gliomas(More)
In the naïve adult rodent eye cell proliferation does not occur. The aim of this in vivo study was to evaluate if quiescent putative progenitor-like cells within the adult mouse eye can be activated by optic nerve (ON) injury. For a comprehensive analysis, three areas were assessed: the ON, the neural retina, and the ciliary body (CB). Two lesion types were(More)
PURPOSE The 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitors, or "statins", are used as cholesterol-lowering agents worldwide. This review, focused on recent experimental and clinical data, summarizes general mechanisms of statin actions underlying neuroprotective effects in the central nervous system (CNS) and presents evidence for(More)
Traditionally, depiction of isolated CNS fiber tracts is achieved by histological post mortem studies. As a tracer-dependent strategy, the calcium analog manganese has proved valuable for in vivo imaging of CNS trajectories, particularly in rats. However, adequate protocols in mice are still rare. To take advantage of the numerous genetic mouse mutants that(More)
One of the obstacles to efficient vector-mediated gene transfer to the CNS is limited transduction of target neurons. The VP22 tegument protein of HSV-1 can cross biological membranes and translocate the VP22 protein from primarily transfected cells to many surrounding cells in vitro. Here, we employed an adenoviral vector coding for a VP22-GFP fusion(More)