Tissue damage after stroke is partly due to disruption of the blood-brain barrier (BBB). Little is known about the role of calcium in modulating BBB disruption. We investigated the effect of hypoxic and aglycemic stress on BBB function and intracellular calcium levels. Bovine brain microvessel endothelial cells were treated with A-23187 to increase intracellular calcium without hypoxia or treat...

Agrin is an extracellular matrix protein that directs neuromuscular junction formation. Early signal transduction events in agrin-mediated postsynaptic differentiation include activation of a receptor tyrosine kinase and phosphorylation of acetylcholine receptors (AChRs), but later steps in this pathway are unknown. Here, we have investigated the role of intracellular calcium in agrin-induced A...

Taste stimuli are detected by taste receptor cells present in the oral cavity using diverse signaling pathways. Some taste stimuli are detected by G protein-coupled receptors (GPCRs) that cause calcium release from intracellular stores, whereas other stimuli depolarize taste cells to cause calcium influx through voltage-gated calcium channels (VGCCs). Although taste cells use two distinct mecha...

BACKGROUND & OBJECTIVES The biochemical mechanisms underlying the development of sensitization-induced airway hyperresponsiveness (AHR) in asthma are poorly defined. Alterations in the regulation of intracellular calcium may play an important role in its pathogenesis. We carried out this study to see the effect of sensitization with ovalbumin on membrane ion fluxes and intracellular calcium in ...

Apicomplexans such as Toxoplasma gondii actively invade host cells using a unique parasite-dependent mechanism termed gliding motility. Calcium-mediated protein secretion by the parasite has been implicated in this process, but the precise role of calcium signaling in motility remains unclear. Here we used calmidazolium as a tool to stimulate intracellular calcium fluxes and found that this dru...

Agrin is an extracellular matrix protein that directs neuromuscular junction formation. Early signal transduction events in agrin-mediated postsynaptic differentiation include activation of a receptor tyrosine kinase and phosphorylation of AChRs , but later steps in this pathway are unknown. Here, we have investigated the role of intracellular calcium in agrin-induced AChR clustering on culture...

We have hypothesized that an intracellular calcium deficit may occur in the early phase of Alzheimer's disease (AD). This hypothesis has two important corollaries. First, it predicts that elevation of calcium levels by many calcium agonists, in principle, would have protective effects in the individuals at-risk to AD. Second, it implies that an artificial decrease of the calcium levels by the u...

In cardiovascular diseases, endothelin type B (ET(B)) receptors in arterial smooth muscle cells are upregulated. The present study revealed that organ culture of rat mesenteric artery segments enhanced endothelin ET(B) receptor-mediated contraction paralleled with increase in the receptor mRNA and protein expressions. The endothelin ET(B) receptor-mediated contraction was associated with increa...

Intracellular calcium signaling is critical for initiating and sustaining diverse cellular functions including transcription, synaptic signaling, muscle contraction, apoptosis and fertilization. Trans-membrane 203 (TMEM203) was identified here in cDNA overexpression screens for proteins capable of modulating intracellular calcium levels using activation of a calcium/calcineurin regulated transc...