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Background and Aims Root observation windows (RW) installed in the field provide a tool for non-destructive monitoring of root development and rhizosphere processes. However, the highly invasive installation process, which requires cutting soil profiles, may affect plant development and, ultimately, the outcome of the experiments. This study systematically compares plant development with and without the installation of RW. Met...
Acetylcholine, the physiological agonist at all muscarinic receptors, alone (“direct effect”) or after pre-stimulation with isoprenaline (“indirect effect”), is known to reduce the force of contraction (FOC) in human atrial preparations (HAP). We hypothesized that muscarine might act similar to acetylcholine. During open heart surgery for severe coronary heart disease, HAP were obtained. Using digital polymerase chain reaction...
The function importance of serine threonine phosphatases (PP) in the heart is still subject of investigations. For instance, PP5 and PP2C occur in the human heart. It is unclear how they interact in the human heart. In order to obtain a model system, we have crossbred mice with heart-specific overexpression of PP2C or PP5 to obtain wild-type mice (WT), PP2C transgenic mice (PP2C-TG), PP5 transgenic mice (PP5-TG), and PP2CxPP5...
Protein phosphatase 2A (PP2A) accounts for approximately half of all serine/threonine phosphatase activity in the mammalian heart. We hypothesised that PP2A, through dephosphorylation of key regulatory enzymes, modulates cardiac glucose uptake and metabolism in vivo. Using positron emission tomography (PET), we studied the uptake of 2-[ 18 F]fluoro-2-deoxy-D-glucose ([ 18 F]FDG) in living mice with cardiac-specific overexpress...
There are five muscarinic receptor subtypes expressed in the human heart. The main subtype is the M 2 -muscarinic receptor. We hypothesized that overexpression of the M 2 -muscarinic receptor should augment any contractile effects that are M 2 -muscarinic receptor–mediated. Therefore, we generated a transgenic mouse with overexpression of the human M 2 -muscarinic receptor under the control of the heart-specific α-myosin heavy...
Intraspecific differences in leaf decomposition and associated traits in closely related Carex species: a microcosm experimentNARA Subscribed
Litter decomposition is a fundamental process in carbon and nutrient cycling in terrestrial ecosystems. In a microcosm experiment we investigated the determinants of leaf decomposition with consideration of the 'afterlife’ effect hypothesis, which suggests a connection between green leaf traits and the decomposability of leaf material. We collected senesced litter and living leaves of individuals of four Carex species widely d...
Stimulation of histamine H1-receptors produces a positive inotropic effect in the human atriumNARA Subscribed
There is a controversy whether histamine H 1 -receptor activation raises or lowers or does not affect contractility in the human heart. Therefore, we studied stimulation of H 1 -receptors in isolated electrically stimulated (one beat per second) human atrial preparations (HAP). For comparison, we measured force of contraction in left atrial preparations (LA) from mice with overexpression of the histamine H 1 -receptor in the h...
Initial characterization of a transgenic mouse with overexpression of the human D1-dopamine receptor in the heartNARA Subscribed
Dopamine can exert effects in the mammalian heart via five different dopamine receptors. There is controversy whether dopamine receptors increase contractility in the human heart. Therefore, we have generated mice that overexpress the human D 1 -dopamine receptor in the heart (D 1 -TG) and hypothesized that dopamine increases force of contraction and beating rate compared to wild-type mice (WT). In D 1 -TG hearts, we ascertain...
Toxicity of octameric elemental sulphur in aquatic sedimentsNARA Subscribed
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