Biomaterial Database

Whole-cell recordings of inwardly rectifying K+ currents activated by 5-HT1A receptors on dorsal raphe neurones of the adult rat. 1993

N J Penington, and J S Kelly, and A P Fox

Department of Pharmacological and Physiological Sciences, University of Chicago, IL 60637.

1. An inwardly rectifying K+ current activated by serotonin (5-HT) was recorded from acutely isolated adult dorsal raphe (DR) neurones using the whole-cell recording mode of the patch clamp technique. 2. The 5-HT-induced K+ current (I5-HT) was only visible at an [K+]0 > 5 mM and it was observed in 69% of the cells. 3. The reversal potential for I5-HT was close to the potassium equilibrium potential and was shifted by 51 mV per 10-fold change in [K+]0 indicating that I5-HT was carried predominantly by K+. The chord conductance of I5-HT at -90 mV was proportional to the external [K+] raised to a fractional power. 4. A dose-response relationship revealed that I5-HT was activated with an ED50 of 30 nM. Ba2+ (0.1 mM) blocked I5-HT completely. Spiperone reversibly antagonized the response to 5-HT and 8-OHDPAT (8-hydroxy-2-(di-n-propylamino)tetralin) mimicked the response indicating that the receptor activated was of the 5-HT1A subtype. 5. The response to 5-HT was largely prevented by in vitro pretreatment of the cells with pertussis toxin (PTX) indicating the involvement of a PTX-sensitive G-protein in the transduction mechanism. 6. cAMP and lipoxygenase metabolites, both implicated in the modulation of similar currents in other preparations, were found not to alter the effectiveness of 5-HT. 7. Glibenclamide and tolbutamide, blockers of the ATP-regulated K+ channel, did not reduce the effect of 5-HT in DR neurones. 8. These results show that in acutely isolated adult DR neurones 5-HT activates an inwardly rectifying K+ current and this involves a PTX-sensitive G-protein in the transduction pathway which may interact with the K+ channel directly.

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
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
D009637	Masoprocol	A potent lipoxygenase inhibitor that interferes with arachidonic acid metabolism. The compound also inhibits formyltetrahydrofolate synthetase, carboxylesterase, and cyclooxygenase to a lesser extent. It also serves as an antioxidant in fats and oils.	Nordihydroguaiaretic Acid,(R,S)-4,4'-(2,3-Dimethylbutane-1,4-diyl)bispyrocatechol,Actinex,Dihydronorguaiaretic Acid,Nordihydroguaiaretic Acid, (R,S)-Isomer,meso-Nordihydroguaiaretic Acid,Acid, meso-Nordihydroguaiaretic,meso Nordihydroguaiaretic Acid
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
D011188	Potassium	An element in the alkali group of metals with an atomic symbol K, atomic number 19, and atomic weight 39.10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the WATER-ELECTROLYTE BALANCE.
D011903	Raphe Nuclei	Collections of small neurons centrally scattered among many fibers from the level of the TROCHLEAR NUCLEUS in the midbrain to the hypoglossal area in the MEDULLA OBLONGATA.	Caudal Linear Nucleus of the Raphe,Interfascicular Nucleus,Nucleus Incertus,Rostral Linear Nucleus of Raphe,Rostral Linear Nucleus of the Raphe,Superior Central Nucleus,Central Nucleus, Superior,Incertus, Nucleus,Nuclei, Raphe,Nucleus, Interfascicular,Nucleus, Raphe,Nucleus, Superior Central,Raphe Nucleus
D011985	Receptors, Serotonin	Cell-surface proteins that bind SEROTONIN and trigger intracellular changes which influence the behavior of cells. Several types of serotonin receptors have been recognized which differ in their pharmacology, molecular biology, and mode of action.	5-HT Receptor,5-HT Receptors,5-Hydroxytryptamine Receptor,5-Hydroxytryptamine Receptors,Receptors, Tryptamine,Serotonin Receptor,Serotonin Receptors,Tryptamine Receptor,Tryptamine Receptors,Receptors, 5-HT,Receptors, 5-Hydroxytryptamine,5 HT Receptor,5 HT Receptors,5 Hydroxytryptamine Receptor,5 Hydroxytryptamine Receptors,Receptor, 5-HT,Receptor, 5-Hydroxytryptamine,Receptor, Serotonin,Receptor, Tryptamine,Receptors, 5 HT,Receptors, 5 Hydroxytryptamine
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
D005905	Glyburide	An antidiabetic sulfonylurea derivative with actions like those of chlorpropamide	Glibenclamide,Daonil,Diabeta,Euglucon 5,Euglucon N,Glybenclamide,HB-419,HB-420,Maninil,Micronase,Neogluconin,HB 419,HB 420,HB419,HB420
D000242	Cyclic AMP	An adenine nucleotide containing one phosphate group which is esterified to both the 3'- and 5'-positions of the sugar moiety. It is a second messenger and a key intracellular regulator, functioning as a mediator of activity for a number of hormones, including epinephrine, glucagon, and ACTH.	Adenosine Cyclic 3',5'-Monophosphate,Adenosine Cyclic 3,5 Monophosphate,Adenosine Cyclic Monophosphate,Adenosine Cyclic-3',5'-Monophosphate,Cyclic AMP, (R)-Isomer,Cyclic AMP, Disodium Salt,Cyclic AMP, Monoammonium Salt,Cyclic AMP, Monopotassium Salt,Cyclic AMP, Monosodium Salt,Cyclic AMP, Sodium Salt,3',5'-Monophosphate, Adenosine Cyclic,AMP, Cyclic,Adenosine Cyclic 3',5' Monophosphate,Cyclic 3',5'-Monophosphate, Adenosine,Cyclic Monophosphate, Adenosine,Cyclic-3',5'-Monophosphate, Adenosine,Monophosphate, Adenosine Cyclic