Julia V Gerasimenko

Learn More
Agonist-evoked cytosolic Ca(2+) spikes in mouse pancreatic acinar cells are specifically initiated in the apical secretory pole and are mostly confined to this region. The role played by mitochondria in this process has been investigated. Using the mitochondria-specific fluorescent dyes MitoTracker Green and Rhodamine 123, these organelles appeared as a(More)
Nuclear calcium signalling has been a controversial battlefield for many years and the question of how permeable the nuclear pore complexes (NPCs) are to Ca2+ has been the subject of a particularly hot dispute. Recent data from isolated nuclei suggest that the NPCs are open even after depletion of the Ca2+ store in the nuclear envelope. Other research has(More)
Uptake and release of Ca2+ from isolated liver nuclei were studied with fluorescent probes. We show with the help of digital imaging and confocal microscopy that the Ca(2+)-sensitive fluorescent probe Fura 2 is concentrated in or around the nuclear envelope and that the distribution of Fura 2 fluorescence is similar to that of an endoplasmic reticulum(More)
Ca2+ release from the envelope of isolated pancreatic acinar nuclei could be activated by nicotinic acid adenine dinucleotide phosphate (NAADP) as well as by inositol 1,4,5-trisphosphate (IP3) and cyclic ADP-ribose (cADPR). Each of these agents reduced the Ca2+ concentration inside the nuclear envelope, and this was associated with a transient rise in the(More)
Acute pancreatitis is a human disease in which the pancreatic pro-enzymes, packaged into the zymogen granules of acinar cells, become activated and cause autodigestion. The main causes of pancreatitis are alcohol abuse and biliary disease. A considerable body of evidence indicates that the primary event initiating the disease process is the excessive(More)
We have investigated in detail the role of intra-organelle Ca2+ content during induction of apoptosis by the oxidant menadione while changing and monitoring the Ca2+ load of endoplasmic reticulum (ER), mitochondria, and acidic organelles. Menadione causes production of reactive oxygen species, induction of oxidative stress, and subsequently apoptosis. In(More)
Hormones and neurotransmitters mobilize Ca(2+) from the endoplasmic reticulum via inositol trisphosphate (IP(3)) receptors, but how a single target cell encodes different extracellular signals to generate specific cytosolic Ca(2+) responses is unknown. In pancreatic acinar cells, acetylcholine evokes local Ca(2+) spiking in the apical granular pole, whereas(More)
In pancreatic acinar cells low (physiological) agonist concentrations evoke cytosolic Ca2+ spikes specifically in the apical secretory pole that contains a high density of secretory (zymogen) granules (ZGs). Inositol 1,4,5-trisphosphate (IP3) is believed to release Ca2+ from the endoplasmic reticulum, but we have now tested whether the Ca(2+)-releasing(More)
We have investigated the spreading of cytosolic Ca2+ signals generated by acetylcholine stimulation (using either microionophoresis or pressure application) of isolated pancreatic acinar cells (or small cell clusters) using confocal microscopy of Ca2+-sensitive fluorescence (fura red). We have been particularly interested in the effects of short vigorous(More)
A number of specific cellular Ca2+ uptake pathways have been described in many different cell types [1] [2] [3]. The possibility that substantial quantities of Ca2+ could be imported via endocytosis has essentially been ignored, although it has been recognized that endosomes can store Ca2+ [4] [5]. Exocrine cells can release significant amounts of Ca2+ via(More)