Differentiation of answer of glioma C6 cells to SERCA pump inhibitors by actin disorganization.

Capacitative calcium entry, usually evoked by receptor-ligand binding, may be also studied in the model system of calcium release after SERCA pump inhibition. We have previously found that disorganization of actin cytoskeleton has no effect on calcium influx into glioma C6 cells after thapsigargin administration [Biochem. Biophys.

Modulation by cationic amphiphilic drugs of serine base-exchange, phosholipase d and intracellular calcium homeostasis in glioma C6 cells.

We aimed to assess the effect of three drugs belonging to amphiphilic cations, imipramine, amitriptyline and propranolol, on lipid synthesis and intracellular calcium homeostasis in glioma C6 cells. Antidepressants, imipramine and amitriptyline, had a stimulatory effect on [14C]serine incorporation into phosphatidylserine. Similar effect was induced by propranolol, antidysrhythmic drug and an antagonist of beta-adrenergic receptor, but not by isoproterenol, a selective agonist of this receptor.

ADP-evoked phospholipase C stimulation and adenylyl cyclase inhibition in glioma C6 cells occur through two distinct nucleotide receptors, P2Y(1) and P2Y(12).

In this study we characterized the subtypes of nucleotide P2Y receptors that respond to ADP in glioma C6 cells. Direct visualization of phosphatidylinositol 4,5-bisphosphate at the cell surface revealed that extracellular ADP activates phospholipase C (PLC). Knock-down of P2Y(1) receptor with antisense oligonucleotide, as well as treatment with MRS2179 and pyridoxal-phosphate-6-azophenyl-2',4'-disulfonic acid (P2Y(1) antagonists), attenuates receptor-mediated PLC activity.

Ca(2+) response to cADPr during maturation and fertilization of starfish oocytes.

During the reinitiation of the meiotic cycle (maturation) induced by the hormone 1-methyladenine (1-MA), starfish oocytes undergo structural and biochemical changes in preparation for successful fertilization. Previous work has shown that the sensitivity of internal Ca(2+) stores to InsP(3) increases during maturation of the oocytes. Since Astropecten auranciacus oocytes also respond to cADPr, we have studied whether the response to cADPr also changes during maturation.