extracellular ca 2+ concentration ([ca2+]o) may be one of the factors affecting atrial natriuretic factor (anf) release. in the previous studies, there are opposite reports about the effect of [ca2+]o on anf secretion. therefore, the effect of [ca2+]o depletion on anf secretion and gene expression was studied in the present research. isolated right atria from rats were perfused for 6 and 2 hour...

Background: Parthenogenetic activation is a possible way to produce homogeneous embryos with the some ploidy. Probably such embryos could be used in other areas of biotechnology. Calcium signals are known as important regulators of oocyte activation. Extracellular calcium is required for initiation of meiotic resumption and development. Calcium ionophore A23187 is known to elevate intracellular...

The cloning of a G protein-coupled extracellular Ca(2+) (Ca(o)(2+))-sensing receptor (CaR) has elucidated the molecular basis for many of the previously recognized effects of Ca(o)(2+) on tissues that maintain systemic Ca(o)(2+) homeostasis, especially parathyroid chief cells and several cells in the kidney. The availability of the cloned CaR enabled the development of DNA and antibody probes f...

Background: Oocyte maturation is usually defined as the period of progression from the first to the second meiotic arrest and involves coordinated nuclear and cytoplasmic modification. Ca2+ signals are known as important regulators of oocyte maturation. Extracellular Ca2+ is important for first polar body formation, normal meiosis kinetics, and for preserving the chromosome and spindle configur...

Previously, we reported that endoplasmic reticulum calcium stores were a direct target for paclitaxel initiation of apoptosis. Furthermore, the actions of paclitaxel attenuated Bcl-2 resistance to apoptosis through endoplasmic reticulum-mediated calcium release. To better understand the calcium-regulated mechanisms of paclitaxel-induced apoptosis in breast cancer cells, we investigated the role...

Transient changes of extracellular free calcium in rabbit ventricular muscle under nonsteady state conditions were measured with double-barreled calcium microelectrodes. Resumption of stimulation after a rest interval produces a cumulative decrease of extracellular free calcium often by more than 10% (with bulk extracellular free calcium = 0.2 HIM) The extracellular free calcium returns to the ...

Transient changes of extracellular free calcium in rabbit ventricular muscle under nonsteady state conditions were measured with double-barreled calcium microelectrodes. Resumption of stimulation after a rest interval produces a cumulative decrease of extracellular free calcium often by more than 10% (with bulk extracellular free calcium = 0.2 mM). The extracellular free calcium returns to the ...

Extracellular calcium is critical for many neural functions, including neurotransmission, cell adhesion, and neural plasticity. Experiments have shown that normal neural activity is associated with changes in extracellular calcium, which has motivated recent computational work that employs such fluctuations in an information-bearing role. This possibility suggests that a new style of computing ...