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The Expert has conducted intensive research in vascular biology including modulation of vascular tone by regulation of calcium homeostasis. Calcium (Ca2+) enters the cytoplasm of vascular smooth muscle and endothelial cells via various pathways (calcium channels, intracellular calcium stores) and dysfunction of these pathways contribute often to vascular diseases such as hypertension.

One of his research projects was to determine how Ca2+ dysregulation can contribute to the pathophysiology of pre-eclampsia, a serious complication during the mid/third trimester of pregnancies. By using calcium imaging and electrophysiological techniques he characterized Ca2+ signalling in vascular endothelial and smooth muscle cells.

As Ca2+ is one of the key regulators of nitric oxide (NO) synthase NOS he additionally analyzed NOS signalling in tissue obtained from pregnant women affected by pre-eclampsia.

The Expert is currently investigating the mechanisms underlying various neurodegenerative diseases such as Alzheimer’s (AD), Parkinson (PD), Huntington disease (HD) or Prion disease all of which exhibit a progressing neuronal cell death. Here he is interested in modulation of ion channels (potassium, sodium, calcium) contributing to neuronal dysfunction. NO production from inflammation and resulting oxidative stress is also a significant factor in AD, PD, multiple sclerosis (MS) and HD and currently studies using cell culture and Drosophila models of HD being conducted.

The Expert has conducted intensive research in vascular biology including modulation of vascular tone by regulation of calcium homeostasis. Calcium (Ca2+) enters the cytoplasm of vascular smooth muscle and endothelial cells via various pathways (calcium channels, intracellular calcium stores) and dysfunction of these pathways contribute often to vascular diseases such as hypertension.

The Expert is investigating physiological effect of NO on auditory functions. Here he has characterized the involvement of NO in auditory processing as mediated in the auditory brainstem. He is applied a fluorescent method to detect NO levels upon neuronal activity by using a rhodamine-based chromophore diaminorhodamine-4M (DAR-4M). Several different nuclei are involved in sound source localization (medial superior olive (MSO), lateral superior olive (LSO), the superior-paraolivary nucleus (SPN) and nuclei of the lateral lemniscus (NLL)) and signal transmission encoded by action potential firing is depending on the action of various ion channels (e.g. potassium, sodium). His expertise in physiological regulation of these mechanisms has also been extended to investigate pathological alterations occurring during neurodegenerative diseases (e.g. tinnitus). Different potassium channels have been implicated in degenerative/apoptotic signalling and by using electrophysiological methods (patch clamp technique) the involvement of these ion channels can be characterized.

A general involvement of nitric oxide (NO) has been documented in many neurodegenerative disorders and his primary aim is to investigate how this free radical gas is involved in oxidative stress-mediated neuronal cell death. The amount of cellular oxidative stress is determined by a balance of physiological antioxidant systems (Superoxide Dismutase, Catalase, Glutathione Peroxidase) and the generation of reactive oxygen species (e.g. Superoxide generated by Mitochondria, Xanthine Oxidase, NAD(P)H Oxidase, NOS). Thus, if this balance is shifted towards enhanced generation of reactive oxygen species (ROS) with lacking antioxidant defense, cells experience detrimental effects such as lipid peroxidation or DNA damage.