Biomaterial Database

Pertussis-toxin-sensitive inhibition by (-) baclofen of Ca signals in bovine chromaffin cells. 1991

P Doroshenko, and E Neher

Max-Planck-Institut für biophysikalische Chemie, Göttingen, Federal Republic of Germany.

Ca signals in bovine adrenal chromaffin cells were studied both in Fura-2/AM-loaded intact cells, and in voltage-clamped cells under whole-cell patch-clamp conditions. The effects of gamma-aminobutyric acid b subtype (GABAb) receptor activation on K(+)-depolarization-induced signals and on voltage-activated Ca2+ currents were investigated. Both GABA (20 microM) plus bicuculline (20 microM) and (-)baclofen (20-100 microM), effectively inhibited the Ca signal in intact cells. The effects caused by baclofen continued to develop during the time interval between two successive stimuli. The restoration of the Ca signal during washout of baclofen was also delayed and continued in some experiments for 10-20 min. The inhibitory effect of baclofen on the Ca signal was eliminated by pre-treatment of the cells with pertussis toxin (PTX, 1 micrograms/ml, for 4-6 h at 37 degrees C). Baclofen (50 microM) inhibited Ca2+ current in whole-cell mode by at most 20%. The effect developed quickly and was reversible. Infusion into the cells of a non-hydrolyzable analogue of guanosine 5'-triphosphate GTP gamma S (100 microM), led to complete inhibition of the Ca2+ conductance and of voltage-evoked intracellular Ca ([CA]i) transients within 2 min. In paired cells intracellularly perfused with GTP gamma S-free solution, the Ca2+ current amplitude decreased by only about 30% for 5-6 min. It is concluded that bovine chromaffin cells have functional GABAb receptors the activation of which, mediated by a PTX-sensitive GTP-binding protein, inhibits the evoked increase in cytosolic free Ca2+.(ABSTRACT TRUNCATED AT 250 WORDS)

UI	MeSH Term	Description	Entries
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
D011963	Receptors, GABA-A	Cell surface proteins which bind GAMMA-AMINOBUTYRIC ACID and contain an integral membrane chloride channel. Each receptor is assembled as a pentamer from a pool of at least 19 different possible subunits. The receptors belong to a superfamily that share a common CYSTEINE loop.	Benzodiazepine-Gaba Receptors,GABA-A Receptors,Receptors, Benzodiazepine,Receptors, Benzodiazepine-GABA,Receptors, Diazepam,Receptors, GABA-Benzodiazepine,Receptors, Muscimol,Benzodiazepine Receptor,Benzodiazepine Receptors,Benzodiazepine-GABA Receptor,Diazepam Receptor,Diazepam Receptors,GABA(A) Receptor,GABA-A Receptor,GABA-A Receptor alpha Subunit,GABA-A Receptor beta Subunit,GABA-A Receptor delta Subunit,GABA-A Receptor epsilon Subunit,GABA-A Receptor gamma Subunit,GABA-A Receptor rho Subunit,GABA-Benzodiazepine Receptor,GABA-Benzodiazepine Receptors,Muscimol Receptor,Muscimol Receptors,delta Subunit, GABA-A Receptor,epsilon Subunit, GABA-A Receptor,gamma-Aminobutyric Acid Subtype A Receptors,Benzodiazepine GABA Receptor,Benzodiazepine Gaba Receptors,GABA A Receptor,GABA A Receptor alpha Subunit,GABA A Receptor beta Subunit,GABA A Receptor delta Subunit,GABA A Receptor epsilon Subunit,GABA A Receptor gamma Subunit,GABA A Receptor rho Subunit,GABA A Receptors,GABA Benzodiazepine Receptor,GABA Benzodiazepine Receptors,Receptor, Benzodiazepine,Receptor, Benzodiazepine-GABA,Receptor, Diazepam,Receptor, GABA-A,Receptor, GABA-Benzodiazepine,Receptor, Muscimol,Receptors, Benzodiazepine GABA,Receptors, GABA A,Receptors, GABA Benzodiazepine,delta Subunit, GABA A Receptor,epsilon Subunit, GABA A Receptor,gamma Aminobutyric Acid Subtype A Receptors
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
D002417	Cattle	Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.	Beef Cow,Bos grunniens,Bos indicus,Bos indicus Cattle,Bos taurus,Cow,Cow, Domestic,Dairy Cow,Holstein Cow,Indicine Cattle,Taurine Cattle,Taurus Cattle,Yak,Zebu,Beef Cows,Bos indicus Cattles,Cattle, Bos indicus,Cattle, Indicine,Cattle, Taurine,Cattle, Taurus,Cattles, Bos indicus,Cattles, Indicine,Cattles, Taurine,Cattles, Taurus,Cow, Beef,Cow, Dairy,Cow, Holstein,Cows,Dairy Cows,Domestic Cow,Domestic Cows,Indicine Cattles,Taurine Cattles,Taurus Cattles,Yaks,Zebus
D002478	Cells, Cultured	Cells propagated in vitro in special media conducive to their growth. Cultured cells are used to study developmental, morphologic, metabolic, physiologic, and genetic processes, among others.	Cultured Cells,Cell, Cultured,Cultured Cell
D002838	Chromaffin System	The cells of the body which stain with chromium salts. They occur along the sympathetic nerves, in the adrenal gland, and in various other organs.	Argentaffin System,Argentaffin Systems,Chromaffin Systems,System, Argentaffin,System, Chromaffin,Systems, Argentaffin,Systems, Chromaffin
D005680	gamma-Aminobutyric Acid	The most common inhibitory neurotransmitter in the central nervous system.	4-Aminobutyric Acid,GABA,4-Aminobutanoic Acid,Aminalon,Aminalone,Gammalon,Lithium GABA,gamma-Aminobutyric Acid, Calcium Salt (2:1),gamma-Aminobutyric Acid, Hydrochloride,gamma-Aminobutyric Acid, Monolithium Salt,gamma-Aminobutyric Acid, Monosodium Salt,gamma-Aminobutyric Acid, Zinc Salt (2:1),4 Aminobutanoic Acid,4 Aminobutyric Acid,Acid, Hydrochloride gamma-Aminobutyric,GABA, Lithium,Hydrochloride gamma-Aminobutyric Acid,gamma Aminobutyric Acid,gamma Aminobutyric Acid, Hydrochloride,gamma Aminobutyric Acid, Monolithium Salt,gamma Aminobutyric Acid, Monosodium Salt
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
D001418	Baclofen	A GAMMA-AMINOBUTYRIC ACID derivative that is a specific agonist of GABA-B RECEPTORS. It is used in the treatment of MUSCLE SPASTICITY, especially that due to SPINAL CORD INJURIES. Its therapeutic effects result from actions at spinal and supraspinal sites, generally the reduction of excitatory transmission.	Baclophen,Chlorophenyl GABA,Apo-Baclofen,Atrofen,Ba-34,647,Ba-34647,Baclofen AWD,Baclofène-Irex,Baclospas,CIBA-34,647-BA,Clofen,Gen-Baclofen,Genpharm,Lebic,Lioresal,Liorésal,Nu-Baclo,PCP-GABA,PMS-Baclofen,beta-(Aminomethyl)-4-chlorobenzenepropanoic Acid,beta-(p-Chlorophenyl)-gamma-aminobutyric Acid,AWD, Baclofen,Apo Baclofen,ApoBaclofen,Ba34,647,Ba34647,Baclofène Irex,BaclofèneIrex,CIBA34,647BA,GABA, Chlorophenyl,Gen Baclofen,GenBaclofen,Nu Baclo,NuBaclo,PMS Baclofen,PMSBaclofen
D001640	Bicuculline	An isoquinoline alkaloid obtained from Dicentra cucullaria and other plants. It is a competitive antagonist for GABA-A receptors.	6-(5,6,7,8-Tetrahydro-6-methyl-1,3-dioxolo(4,5-g)isoquinolin-5-yl)furo(3,4-e)1,3-benzodioxol-8(6H)one