Angiotensin II stimulated the breakdown of phosphatidylinositol-4,5-bisphosphate (PIP2) and the generation of inositol trisphosphate (IP3) in cultured rat aortic smooth muscle cells. The decrease in PIP2 and increase in IP3 levels were rapid (measurable at 5 seconds; maximum IP3 levels at 15 seconds). The time course of these changes was comparable to that of angiotensin II-induced increases in...

The Entamoeba histolytica upstream regulatory element 3-binding protein (URE3-BP) binds to the URE3 sequence of the Gal/GalNAc-inhibitable lectin hgl5 and ferredoxin 1 (fdx) gene promoters. This binding can be inhibited in vitro by addition of calcium. Two EF-hand motifs, which are associated with the ability to bind calcium, are present in the amino acid sequence of URE3-BP. Mutation of the se...

In Alzheimer’s disease (AD), abnormal accumulations of fl-amyloid are present in the brain and degenerating neurons exhibit cytoskeletal aberrations (neurofibrillary tangles). Roles for &amyloid in the neuronal degeneration of AD have been suggested based on recent data obtained in rodent studies demonstrating neurotoxic actions of /I-amyloid. However, the cellular mechanism of action of /?-amy...

Both forskolin, the activator of adenylate cyclase, and 8-bromocyclic (cAMP) increase cytosolic calcium levels (measured using Quin 2) and adrenocorticotropin (ACTH) release from a tumor cell line of the mouse anterior pituitary (AtT-20/D16-16). Somatostatin (SRIF) blocks the ACTH release response to each secretagogue but only inhibits forskolin-stimulated calcium mobilization suggesting that S...

BACKGROUND Investigation of the mechanisms of guided cell migration can contribute to our understanding of many crucial biological processes, such as development and regeneration. Endogenous and exogenous direct current electric fields (dcEF) are known to induce directional cell migration, however the initial cellular responses to electrical stimulation are poorly understood. Ion fluxes, beside...

The level of cytoplasmic calcium has been proposed to act as a regulator of acetylcholine receptor synthesis (Betz, H., and J. P. Changeaux (1979) Nature 278: 749-751). However, there is little known about the effect of altered calcium levels on the metabolism of the acetylcholine receptor. We have investigated the effect of decreased extracellular calcium on the metabolism of acetylcholine rec...