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)
In pancreatic acinar cells, low, threshold concentrations of acetylcholine (ACh) or cholecystokinin (CCK) induce repetitive local cytosolic Ca2+ spikes in the apical pole, while higher concentrations elicit global signals. We have investigated the process that transforms local Ca2+ spikes to global Ca2+ transients, focusing on the interactions of multiple… (More)
Recent studies have shown that cytosolic Ca(2+) signals, generated on one side of a nerve growth cone, can induce turning either towards or away from the side of the Ca(2+) signal, depending on the global Ca(2+) level. The results indicate that local Ca(2+) signals may provide important directional cues for axon guidance.
Different hormones and neurotransmitters, using Ca2+ as their intracellular messenger, can generate specific cytosolic Ca2+ signals in different parts of a cell. In mouse pancreatic acinar cells, cytosolic Ca2+ oscillations are triggered by activation of acetylcholine (ACh), cholecystokinin (CCK) and bombesin receptors. Low concentrations of these three… (More)
Cyclic ADP-ribose (cADPR) is a potentially important intracellular Ca2+ releasing messenger [1-5]. In pancreatic acinar cells where intracellular infusion of both inositol trisphosphate (IP3) and cADPR evoke repetitive Ca2+ spiking , the cADPR antagonist 8-NH2-cADPR , which blocks cADPR-evoked but not IP3-evoked Ca2+ spiking, can abolish Ca2+ spiking… (More)
In order to investigate the possible involvement of cyclic ADP ribose as an intracellular messenger for hormone-evoked cytosolic Ca2+ signalling, we performed experiments on intracellularly perfused mouse pancreatic acinar cells. Both a stable inositol 1,4,5 trisphosphate analogue (IP3) and cyclic ADP ribose (cADPR) evoked regular spikes of Ca2+ dependent… (More)
The role of cAMP in the regulation of the high affinity choline uptake (HACU) was investigated in resting and KCl-stimulated rat brain synaptosomes. The data indicate that the permeable cAMP analogue, monobutyryl-8-bromo cAMP, increased dose-dependently the HACU in resting synaptosomes. Treatments of resting synaptosomes by oxotremorine, quinacrine, and… (More)
Axon extension and guidance are clearly very important in the development of the nervous system. A number of intracellular control systems have been implicated in these processes, including protein kinases and phosphatases, as well as cytosolic Ca 2+ signals and intracellular regulators of the actin cytoskeleton [1,2]. Recent results [3,4] have now revealed… (More)