Previously, we have found that intracellular calcium homeostasis is altered in platelets from an experimental model of liver cirrhosis, the bile-duct ligated (BDL) rat; these alterations are compatible with the existence of a hypercoagulable state and related to an enhanced intracellular calcium release evoked by thrombin and an increased amount of calcium stored in the intracellular organelles...

Maintenance of synaptic transmission requires regulation of intracellular Ca(2+) in presynaptic nerve terminals; loss of this regulation at elevated temperatures may cause synaptic failure. Accordingly, we examined the thermosensitivity of presynaptic calcium regulation in Drosophila larval neuromuscular junctions, testing for effects of disrupting calcium clearance. Motor neurons were loaded w...

Rapid and local changes in the concentration of calcium ions can have a dramatic impact on signaling pathways and cell behavior. The papers discussed in this Molecular Biology Select reveal insights into the molecular mediators of calcium signaling in diverse biological contexts, including cell migration, mitochondrial movement, neuronal gene expression, and host responses to invading microorga...

Secretory granules (SGs) sequester significant calcium. Understanding roles for this calcium and potential mechanisms of release is hampered by the difficulty of measuring SG calcium directly in living cells. We adapted the Förster resonance energy transfer-based D1-endoplasmic reticulum (ER) probe to develop a unique probe (D1-SG) to measure calcium and pH in secretory granules. It significant...

Radioactive calcium flux in rabbit aorta was studied to evaluate factors regulating the movement of calcium into and out of the cell. Calcium content was estimated both from (1) the amount of Ca present in the tissue and the specific activity of Ca in the bathing medium, and (2) determination of chemical calcium by atomic absorption spectrophotometry. Calcium efflux was followed by washing aort...

introduction: ca(oh) 2 -containing/forming materials are conventionally used for indirect pulp-capping and are theoretically able to release ca 2+ and oh - ions for hydrolytic dissociation. however, no evidence exists for ion diffusion through the remaining coronal dentin. the aim of this study was to design an innovative experimental set-up to test the ability of ca(oh) 2 -containing and ca(oh...

The production of parathyroid hormone-related protein (PTHrP) is regulated by a variety of hormones and growth factors. Previous research has shown that several PTHrP-producing cells are influenced by extracellular calcium (Ca(2+)(o)) concentration, with elevated levels increasing PTH-like activity released by cultured H500 rat Leydig tumor cells through a post-transcriptional mechanism. We hav...

The significance of calcium soap formation in the inhibition of calcium absorption has been studied in rats. 47Ca labelled soaps of fatty acids were introduced into the duodenum and the absorption of calcium measured after four hours in a whole body counter. The absorption of calcium was inversely correlated with the chain length of the fatty acid varying from 1% for Ca-stearate to 60% for Ca-h...

The activity of calcium-activated chloride channels is controlled through the complex interaction of cellular mechanisms affecting calcium entry, buffering, and extrusion, and an unknown stoichiometric relation between intracellular Ca concentration and Cl channel activation. Here, we show that calcium-activated chloride current [ICl(Ca)] in cone photoreceptors is also highly sensitive to exter...

Calcium signaling is a key regulator of processes important in differentiation. In colon cancer cells differentiation is associated with altered expression of specific isoforms of calcium pumps of the endoplasmic reticulum and the plasma membrane, suggesting that differentiation of colon cancer cells is associated with a major remodeling of calcium homeostasis. Purinergic and neurotensin recept...