Biomaterial Database

Spontaneous transient outward currents: modulation by nociceptin in murine dentate gyrus granule cells. 2001

T Shirasaki, and T Houtani, and T Sugimoto, and H Matsuda

Department of Physiology, Kansai Medical University, Moriguchi, 570-8506, Osaka, Japan.

Spontaneous transient outward currents have been found in peripheral neurons and smooth muscle cells, but rarely in central neurons. Using a nystatin-perforated patch clamp technique, we succeeded in recording spontaneous transient outward currents in mouse dentate gyrus granule cells. Nociceptin/orphanin FQ increased the amplitude and frequency of transient outward currents. We consider modulation of spontaneous transient outward currents to be a new means to regulate cell activity in central neurons, and studied their characteristics and mechanism of augmentation. The whole-cell current-voltage relationship showed outward rectification and the reversal potential was close to the equilibrium potential for K+. The frequency of spontaneous transient outward currents increased at depolarized potentials. Tetraethylammonium, iberiotoxin and a Ca2+ chelator BAPTA-AM inhibited spontaneous transient outward currents. These results suggest the involvement of large-conductance Ca2+-activated K+ channels. Single-channel recordings in the inside-out configuration revealed Ca2+-activated K+ channels with a conductance ranging from 82 to 352 pS. The augmenting effect of nociceptin/orphanin FQ was cancelled by [Phe1psi(CH2-NH)Gly2]Nociceptin(1-13)NH2. Cd2+ did not affect the transient outward currents or augmentation by nociceptin/orphanin FQ. Whereas nociceptin/orphanin FQ, theophylline and cyclic ADP ribose induced transient outward currents with short duration observed under control conditions, inositol 1,4,5-trisphosphate induced transient outward currents with long duration, in addition to those with short duration. Ryanodine inhibited nociceptin/orphanin FQ from augmenting spontaneous transient outward currents. Our data suggest that Ca2+ sparks transiently activate large-conductance Ca2+-activated K+ channels to induce transient outward currents. Nociceptin/orphanin FQ probably sensitizes ryanodine receptors and increases transient outward currents to reduce cell excitability.

UI	MeSH Term	Description	Entries
D008810	Mice, Inbred C57BL	One of the first INBRED MOUSE STRAINS to be sequenced. This strain is commonly used as genetic background for transgenic mouse models. Refractory to many tumors, this strain is also preferred model for studying role of genetic variations in development of diseases.	Mice, C57BL,Mouse, C57BL,Mouse, Inbred C57BL,C57BL Mice,C57BL Mice, Inbred,C57BL Mouse,C57BL Mouse, Inbred,Inbred C57BL Mice,Inbred C57BL Mouse
D008813	Mice, Inbred ICR	An inbred strain of mouse that is used as a general purpose research strain, for therapeutic drug testing, and for the genetic analysis of CARCINOGEN-induced COLON CANCER.	Mice, Inbred ICRC,Mice, ICR,Mouse, ICR,Mouse, Inbred ICR,Mouse, Inbred ICRC,ICR Mice,ICR Mice, Inbred,ICR Mouse,ICR Mouse, Inbred,ICRC Mice, Inbred,ICRC Mouse, Inbred,Inbred ICR Mice,Inbred ICR Mouse,Inbred ICRC Mice,Inbred ICRC Mouse
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
D004553	Electric Conductivity	The ability of a substrate to allow the passage of ELECTRONS.	Electrical Conductivity,Conductivity, Electric,Conductivity, Electrical
D000097629	Nociceptin	A pronociceptive peptide that acts as a specific endogenous agonist to the NOCICEPTIN RECEPTOR.	N-OFQ Peptide,Nociceptin-Orphanin FQ,Orphanin FQ
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
D015221	Potassium Channels	Cell membrane glycoproteins that are selectively permeable to potassium ions. At least eight major groups of K channels exist and they are made up of dozens of different subunits.	Ion Channels, Potassium,Ion Channel, Potassium,Potassium Channel,Potassium Ion Channels,Channel, Potassium,Channel, Potassium Ion,Channels, Potassium,Channels, Potassium Ion,Potassium Ion Channel
D051379	Mice	The common name for the genus Mus.	Mice, House,Mus,Mus musculus,Mice, Laboratory,Mouse,Mouse, House,Mouse, Laboratory,Mouse, Swiss,Mus domesticus,Mus musculus domesticus,Swiss Mice,House Mice,House Mouse,Laboratory Mice,Laboratory Mouse,Mice, Swiss,Swiss Mouse,domesticus, Mus musculus
D018847	Opioid Peptides	The endogenous peptides with opiate-like activity. The three major classes currently recognized are the ENKEPHALINS, the DYNORPHINS, and the ENDORPHINS. Each of these families derives from different precursors, proenkephalin, prodynorphin, and PRO-OPIOMELANOCORTIN, respectively. There are also at least three classes of OPIOID RECEPTORS, but the peptide families do not map to the receptors in a simple way.	Opiates, Endogenous,Endogenous Opiates,Opiate Peptides,Opioid Peptide,Peptide, Opioid,Peptides, Opiate,Peptides, Opioid
D018891	Dentate Gyrus	GRAY MATTER situated above the GYRUS HIPPOCAMPI. It is composed of three layers. The molecular layer is continuous with the HIPPOCAMPUS in the hippocampal fissure. The granular layer consists of closely arranged spherical or oval neurons, called GRANULE CELLS, whose AXONS pass through the polymorphic layer ending on the DENDRITES of PYRAMIDAL CELLS in the hippocampus.	Dentate Fascia,Fascia Dentata,Gyrus Dentatus,Area Dentata,CA4 Field of Hippocampal Formation,CA4 Region, Hippocampal,CA4 of Lorente de No,Cornu Ammonis 4 Area,Hilus Gyri Dentati,Hilus of Dentate Gyrus,Hilus of the Fascia Dentata,Hippocampal CA4 Field,Hippocampal Sector CA4,Area Dentatas,CA4 Field, Hippocampal,CA4, Hippocampal Sector,Dentata, Area,Dentata, Fascia,Dentatas, Area,Fascia, Dentate,Field, Hippocampal CA4,Gyrus, Dentate,Hippocampal CA4 Region,Region, Hippocampal CA4,Sector CA4, Hippocampal