A5072953381- Ion channel regulation and function
- Cardiac electrophysiology and arrhythmias
- Neuroscience and Neuropharmacology Research
- Neuroscience and Neural Engineering
- Receptor Mechanisms and Signaling
- Neuroendocrine regulation and behavior
- Ion Channels and Receptors
- Plant and fungal interactions
- Oral and gingival health research
- Neuropeptides and Animal Physiology
- Cardiomyopathy and Myosin Studies
- Stress Responses and Cortisol
- Nicotinic Acetylcholine Receptors Study
- Carcinogens and Genotoxicity Assessment
- bioluminescence and chemiluminescence research
- Physiological and biochemical adaptations
- Advanced biosensing and bioanalysis techniques
- Probiotics and Fermented Foods
- Hypothalamic control of reproductive hormones
- Cancer-related Molecular Pathways
- Fungal and yeast genetics research
- Advanced Fluorescence Microscopy Techniques
- Genetics and Neurodevelopmental Disorders
- Connective tissue disorders research
- Cystic Fibrosis Research Advances
Universität Hamburg
2009-2022
University Medical Center Hamburg-Eppendorf
2009-2022
Martini-Klinik
2002
Eppendorf (Germany)
1990-1999
University of Michigan–Ann Arbor
1998
University of Potsdam
1995
Leibniz Institute of Virology (LIV)
1995
Hamburg Institut (Germany)
1994
Universität Greifswald
1988
Aberrant activation or inhibition of potassium (K+) currents across the plasma membrane cells has been causally linked to altered neurotransmission, cardiac arrhythmias, endocrine dysfunction, and (more rarely) perturbed developmental processes. The K+ channel subfamily K member 4 (KCNK4), also known as TRAAK (TWIK-related arachidonic acid-stimulated channel), belongs mechano-gated ion channels TRAAK/TREK two-pore-domain (K2P) channels. While K2P are well contribute resting potential...
Gonadotropes are crucial in the control of reproduction but difficult to isolate for functional analysis due their scattered distribution anterior pituitary gland. We devised a binary genetic approach, and describe new mouse model that allows visualization manipulation gonadotrope cells. Using gene targeting embryonic stem cells, we generated mice which Cre recombinase is coexpressed with GnRH receptor, expressed show can direct Cre-mediated recombination yellow fluorescent protein reporter...
1. Voltage‐dependent K+ currents were recorded in cultured tumour‐derived anterior pituitary cells of the rat (GH3 cells) with patch clamp technique. An inward‐rectifying current is described which found to be carried by K+. 2. In isotonic KCl, whole‐cell inward elicited hyperpolarizing pulses from a holding potential ‐40 mV. These showed time‐ and voltage‐dependent inactivation at potentials more negative than ‐60 Inactivation was faster complete larger hyperpolarizations. Recovery also...
We have performed an electrophysiological analysis of the recently cloned Torpedo marmorata Cl- channel. Functional expression channels in oocytes Xenopus laevis previously injected with cRNA yielded outward-rectifying current activated by hyperpolarization. Replacement other anions significantly reduced or inhibited current. Single-channel recordings from cell-attached patches exhibited burst-like channel activity rapid fluctuations between three equally spaced substates (0 pS, 9 and 18...
The KCNH gene family encodes voltage-gated potassium (Kv) channels of the EAG subtype covering three subfamilies (Kv10-12). are involved in control cardiac and neuronal excitation, pathogenic variants genes encoding Kv10 (eag) Kv11 (erg) subfamily members cause a broad clinical spectrum ranging from arrhythmia to neurodevelopmental syndromes. However, no have been hitherto reported for Kv12 (elk) members. Clinical, genomic, functional studies were performed, including voltage-clamp...
1 The mechanism of thyrotropin-releasing hormone (TRH)-induced ether-à-go-go-related gene (erg) K+ current modulation was investigated with the perforated-patch whole-cell technique in clonal somatomammotroph GH3/B6 cells. These cells express a small endogenous erg known to be reduced by TRH. were injected cDNA coding for rat erg1, erg2, erg3 and HERG channels. corresponding currents isolated help specific channel blockers E-4031 dofetilide their biophysical properties determined. 2 TRH (1...
HERG (human ether-à-go-go-related gene) K(+) currents fulfill important ionic functions in cardiac and other excitable cells. In addition, channels influence cell growth migration various types of tumor The mechanisms underlying these are still not resolved. Here, we investigated the role for a line (SW2) derived from small lung cancer (SCLC), malignant variant cancer. two HERG1 isoforms (HERG1a, HERG1b) as well HERG2 HERG3 expressed SW2 Inhibition by acute or sustained application E-4031,...
1 The ether-à-go-go-related gene (erg)-like K+ current in rat lactotrophs from primary culture was characterized and compared with that clonal pituitary cells (GH3/B6). class III antiarrhythmic E-4031 known to block specifically erg channels used isolate the erg-like as E-4031-sensitive current. experiments were performed 150 mM external solution using patch-clamp technique. 2 elicited hyperpolarizing pulses negative -100 mV consisted of a fast pronounced slowly deactivating component....
The expression of mRNA for voltage‐dependent (K v ) and inward‐rectifying K channels ir was studied in clonal rat somato‐mammotroph cells (GH 3 /B 6 cells) pituitary using reverse transcription‐polymerase chain reaction (RT‐PCR). In GH transcripts 16 different channel α ‐subunits (seven Shaker‐related: 1.2, 1.4, 1.5, 2.1, 3.2, 4.1, 5.1; six EAG: eag1, erg1, erg2, elk1–elk3; three KCNQ: KCNQ1–KCNQ3) five 1.1, 2.3, 3.3, 6.2) were found. addition, a short isoform β 2 subunits present. 21 (11...
The voltage‐dependent inwardly rectifying K + current ( I K,IR ) of clonal rat anterior pituitary cells (GH 3 /B 6 was investigated in solutions with physiological gradient using giant polynuclear cells. isolated by the use selective erg ether‐à‐go‐go ‐related gene) channel blocker E‐4031. In external 5 mM solution, carried steady‐state outward potential range between –60 and 0 mV, a maximum amplitude at –40 mV. Negative to equilibrium potential, E , large transient inward currents occurred....
Ether-á-go-go-related gene (erg) channels form one subfamily of the ether-á-go-go (EAG) K(+) and all three erg (erg1-3) are expressed in brain. In present study we characterize a fast current neurones primary culture derived from median part rat embryonic rhombencephala (E15-16). The relatively uniform was regularly found large multipolar serotonergic neurones, occurred also other less well characterized neurones. blocked by antiarrhythmic substance E-4031. Single-cell RT-PCR revealed...
Muscular autorhythmicity provides propulsion of spermatozoa through the epididymal duct, thereby ensuring sperm maturation. In present study, mechanisms underlying bovine spontaneous phasic contractions (SCs) were analyzed by using muscle-tension recording and patch-clamp techniques. SCs recorded from caput, corpus, proximal cauda region found to be predominantly myogenic in origin. Removal luminal fluid induced a burstlike contraction pattern, removal epithelium, complete loss SCs....
Passage of spermatozoa through the epididymis is obligatory for sperm maturation processes and based on spontaneous phasic contractions (SC) epididymal duct. Here, functional role cyclic GMP (cGMP) signaling in modulating SC bovine caput corpus region was examined by muscle tension recording immunological autoradiographic techniques. The cGMP-analog 8-bromo (Br)-cGMP, as well nitric oxide (NO) donor sodium nitroprusside natriuretic peptides (NPs) atrial NP C-type NP, displayed distally...
The expression and functional role of ether-à-go-go-related gene (erg) K+ channels were examined in the bovine epididymal duct. Sperm transit through duct relies on spontaneous phasic contractions (SC) peritubular smooth muscle wall. Isometric tension studies revealed SC-enhancing effects erg channel blockers E-4031, dofetilide, cisapride, haloperidol SC-suppressing activator NS-1643. In corpus epididymidis, EC50 values 32 nM 8.3 microM determined for E-4031 NS-1643, respectively. was also...