Biomaterial Database

Angiotensin II inhibits calcium and M current channels in rat sympathetic neurons via G proteins. 1994

M S Shapiro, and L P Wollmuth, and B Hille

Department of Physiology and Biophysics, University of Washington, Seattle 98195.

We characterized inhibition of N-type Ca2+ and M current K+ channels in rat superior cervical ganglion neurons by angiotensin II (angioII) using the patch clamp. Of 120 neurons, 97 showed inhibition of ICa (mean 32%), which was slow in onset and very slow to reverse under whole-cell recording conditions. This inhibition was blocked by the AT1 receptor antagonist losartan, attenuated by inclusion of 2 mM GDP-beta-S in the pipette, mostly pertussis toxin insensitive, half-sensitive to N-ethylmaleimide, and wholly voltage independent. With 20 mM instead of 0.1 mM BAPTA in the pipette, the inhibition was strongly attenuated; however, we detected no angioII-induced [Ca2+]i signal using the fluorescent indicator indo-1. IBa from cell-attached patches was reduced by bath-applied angioII (mean 33%), suggesting use of a diffusible cytoplasmic messenger. M currents were inhibited by angioII in 8 of 11 neurons (mean 50%) cultured overnight. Hence, a second agonist, angioII, may share the slow, second messenger-utilizing, pertussis toxin-insensitive signaling pathway used by muscarinic agonists.

UI	MeSH Term	Description	Entries
D007093	Imidazoles	Compounds containing 1,3-diazole, a five membered aromatic ring containing two nitrogen atoms separated by one of the carbons. Chemically reduced ones include IMIDAZOLINES and IMIDAZOLIDINES. Distinguish from 1,2-diazole (PYRAZOLES).
D007211	Indoles	Benzopyrroles with the nitrogen at the number one carbon adjacent to the benzyl portion, in contrast to ISOINDOLES which have the nitrogen away from the six-membered ring.
D007473	Ion Channels	Gated, ion-selective glycoproteins that traverse membranes. The stimulus for ION CHANNEL GATING can be due to a variety of stimuli such as LIGANDS, a TRANSMEMBRANE POTENTIAL DIFFERENCE, mechanical deformation or through INTRACELLULAR SIGNALING PEPTIDES AND PROTEINS.	Membrane Channels,Ion Channel,Ionic Channel,Ionic Channels,Membrane Channel,Channel, Ion,Channel, Ionic,Channel, Membrane,Channels, Ion,Channels, Ionic,Channels, Membrane
D007700	Kinetics	The rate dynamics in chemical or physical systems.
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
D008856	Microscopy, Fluorescence	Microscopy of specimens stained with fluorescent dye (usually fluorescein isothiocyanate) or of naturally fluorescent materials, which emit light when exposed to ultraviolet or blue light. Immunofluorescence microscopy utilizes antibodies that are labeled with fluorescent dye.	Fluorescence Microscopy,Immunofluorescence Microscopy,Microscopy, Immunofluorescence,Fluorescence Microscopies,Immunofluorescence Microscopies,Microscopies, Fluorescence,Microscopies, Immunofluorescence
D009474	Neurons	The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the NERVOUS SYSTEM.	Nerve Cells,Cell, Nerve,Cells, Nerve,Nerve Cell,Neuron
D010566	Virulence Factors, Bordetella	A set of BACTERIAL ADHESINS and TOXINS, BIOLOGICAL produced by BORDETELLA organisms that determine the pathogenesis of BORDETELLA INFECTIONS, such as WHOOPING COUGH. They include filamentous hemagglutinin; FIMBRIAE PROTEINS; pertactin; PERTUSSIS TOXIN; ADENYLATE CYCLASE TOXIN; dermonecrotic toxin; tracheal cytotoxin; Bordetella LIPOPOLYSACCHARIDES; and tracheal colonization factor.	Bordetella Virulence Factors,Agglutinogen 2, Bordetella Pertussis,Bordetella Virulence Determinant,LFP-Hemagglutinin,LP-HA,Leukocytosis-Promoting Factor Hemagglutinin,Lymphocytosis-Promoting Factor-Hemagglutinin,Pertussis Agglutinins,Agglutinins, Pertussis,Determinant, Bordetella Virulence,Factor Hemagglutinin, Leukocytosis-Promoting,Factor-Hemagglutinin, Lymphocytosis-Promoting,Factors, Bordetella Virulence,Hemagglutinin, Leukocytosis-Promoting Factor,LFP Hemagglutinin,LP HA,Leukocytosis Promoting Factor Hemagglutinin,Lymphocytosis Promoting Factor Hemagglutinin,Virulence Determinant, Bordetella
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
D004533	Egtazic Acid	A chelating agent relatively more specific for calcium and less toxic than EDETIC ACID.	EGTA,Ethylene Glycol Tetraacetic Acid,EGATA,Egtazic Acid Disodium Salt,Egtazic Acid Potassium Salt,Egtazic Acid Sodium Salt,Ethylene Glycol Bis(2-aminoethyl ether)tetraacetic Acid,Ethylenebis(oxyethylenenitrile)tetraacetic Acid,GEDTA,Glycoletherdiamine-N,N,N',N'-tetraacetic Acid,Magnesium-EGTA,Tetrasodium EGTA,Acid, Egtazic,EGTA, Tetrasodium,Magnesium EGTA