Biomaterial Database

Release of Ca2+ from intracellular store in smooth muscle cells of rat portal vein by ATP-induced Ca2+ entry. 1994

P Pacaud, and G Grégoire, and G Loirand

Laboratoire de Physiologie, Faculté de médecine Victor Pachon, Université de Bordeaux II, France.

1. The action of adenosine 5'-triphosphate (ATP, 10 microM) was studied in single patch-clamped smooth muscle cells of rat portal vein where the free internal Ca2+ concentration in the cell (Cai) was estimated by the emission from the dye indo-1. 2. In the presence of 20 microM gallopamil (D600), a blocker of voltage-dependent Ca2+ channels, ATP applied to cells held at a holding potential of -60 mV evoked a transient inward current and an increase in Cai. 3. The rise in Cai evoked by ATP was completely suppressed in the absence of external Ca2+ although a transient inward current was still observed. 4. ATP-induced responses were not modified by the addition of the inositol 1,4,5-trisphosphate receptor antagonist, heparin (1 mM) in the pipette solution. 5. In the presence of caffeine (5 mM) or ryanodine (100 microM) in the pipette solution, which deplete the intracellular Ca2+ store, the ATP-induced Cai rise was greatly reduced. 6. Our results suggest that in single cells from rat portal vein, ATP releases Ca2+ from intracellular stores without involving InsP3, but via a Ca2+ release mechanism activated by Ca2+ influx through ATP-gated channels.

UI	MeSH Term	Description	Entries
D008564	Membrane Potentials	The voltage differences across a membrane. For cellular membranes they are computed by subtracting the voltage measured outside the membrane from the voltage measured inside the membrane. They result from differences of inside versus outside concentration of potassium, sodium, chloride, and other ions across cells' or ORGANELLES membranes. For excitable cells, the resting membrane potentials range between -30 and -100 millivolts. Physical, chemical, or electrical stimuli can make a membrane potential more negative (hyperpolarization), or less negative (depolarization).	Resting Potentials,Transmembrane Potentials,Delta Psi,Resting Membrane Potential,Transmembrane Electrical Potential Difference,Transmembrane Potential Difference,Difference, Transmembrane Potential,Differences, Transmembrane Potential,Membrane Potential,Membrane Potential, Resting,Membrane Potentials, Resting,Potential Difference, Transmembrane,Potential Differences, Transmembrane,Potential, Membrane,Potential, Resting,Potential, Transmembrane,Potentials, Membrane,Potentials, Resting,Potentials, Transmembrane,Resting Membrane Potentials,Resting Potential,Transmembrane Potential,Transmembrane Potential Differences
D009131	Muscle, Smooth, Vascular	The nonstriated involuntary muscle tissue of blood vessels.	Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D011169	Portal Vein	A short thick vein formed by union of the superior mesenteric vein and the splenic vein.	Portal Veins,Vein, Portal,Veins, Portal
D002118	Calcium	A basic element found in nearly all tissues. It is a member of the alkaline earth family of metals with the atomic symbol Ca, atomic number 20, and atomic weight 40. Calcium is the most abundant mineral in the body and combines with phosphorus to form calcium phosphate in the bones and teeth. It is essential for the normal functioning of nerves and muscles and plays a role in blood coagulation (as factor IV) and in many enzymatic processes.	Coagulation Factor IV,Factor IV,Blood Coagulation Factor IV,Calcium-40,Calcium 40,Factor IV, Coagulation
D000255	Adenosine Triphosphate	An adenine nucleotide containing three phosphate groups esterified to the sugar moiety. In addition to its crucial roles in metabolism adenosine triphosphate is a neurotransmitter.	ATP,Adenosine Triphosphate, Calcium Salt,Adenosine Triphosphate, Chromium Salt,Adenosine Triphosphate, Magnesium Salt,Adenosine Triphosphate, Manganese Salt,Adenylpyrophosphate,CaATP,CrATP,Manganese Adenosine Triphosphate,MgATP,MnATP,ATP-MgCl2,Adenosine Triphosphate, Chromium Ammonium Salt,Adenosine Triphosphate, Magnesium Chloride,Atriphos,Chromium Adenosine Triphosphate,Cr(H2O)4 ATP,Magnesium Adenosine Triphosphate,Striadyne,ATP MgCl2
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D012433	Ryanodine	A methylpyrrole-carboxylate from RYANIA that disrupts the RYANODINE RECEPTOR CALCIUM RELEASE CHANNEL to modify CALCIUM release from SARCOPLASMIC RETICULUM resulting in alteration of MUSCLE CONTRACTION. It was previously used in INSECTICIDES. It is used experimentally in conjunction with THAPSIGARGIN and other inhibitors of CALCIUM ATPASE uptake of calcium into SARCOPLASMIC RETICULUM.
D015544	Inositol 1,4,5-Trisphosphate	Intracellular messenger formed by the action of phospholipase C on phosphatidylinositol 4,5-bisphosphate, which is one of the phospholipids that make up the cell membrane. Inositol 1,4,5-trisphosphate is released into the cytoplasm where it releases calcium ions from internal stores within the cell's endoplasmic reticulum. These calcium ions stimulate the activity of B kinase or calmodulin.	1,4,5-InsP3,Inositol 1,4,5-Triphosphate,Myo-Inositol 1,4,5-Trisphosphate,1,4,5-IP3,Myoinositol 1,4,5-Triphosphate
D015640	Ion Channel Gating	The opening and closing of ion channels due to a stimulus. The stimulus can be a change in membrane potential (voltage-gated), drugs or chemical transmitters (ligand-gated), or a mechanical deformation. Gating is thought to involve conformational changes of the ion channel which alters selective permeability.	Gating, Ion Channel,Gatings, Ion Channel,Ion Channel Gatings
D017208	Rats, Wistar	A strain of albino rat developed at the Wistar Institute that has spread widely at other institutions. This has markedly diluted the original strain.	Wistar Rat,Rat, Wistar,Wistar Rats