Okadaic acid and calyculin A enhance the effect of thyrotropin-releasing hormone on GH3 rat anterior pituitary cells excitability. 1992

L M Delgado, and P de la Peña, and D del Camino, and F Barros
Departamento de Biología Funcional, Facultad de Medicina, Universidad de Oviedo, Spain.

Thyrotropin-releasing hormone (TRH) causes a transient hyperpolarization followed by several minutes of increased action potential frequency in patch-perforated current-clamped GH3 cells. Treatment of cells for 5 min with either 2 or 100 nM of the protein phosphatase inhibitor okadaic acid does not affect electrical activity of the cells, but potentiates the enhancement of action potential frequency elicited by a subsequent addition of TRH. Alternatively, 100 nM (but not 2 nM) of okadaic acid added during the second phase of TRH action, further increases the frequency of firing above that produced by the hormone. Similar effects to those of 2 nM okadaic acid are observed with 20 nM calyculin A. These data suggest that a protein phosphatase plays a major role in regulating the delayed effects of TRH on cell excitability in GH3 cells.

UI MeSH Term Description Entries
D007476 Ionophores Chemical agents that increase the permeability of biological or artificial lipid membranes to specific ions. Most ionophores are relatively small organic molecules that act as mobile carriers within membranes or coalesce to form ion permeable channels across membranes. Many are antibiotics, and many act as uncoupling agents by short-circuiting the proton gradient across mitochondrial membranes. Ionophore
D008387 Marine Toxins Toxic or poisonous substances elaborated by marine flora or fauna. They include also specific, characterized poisons or toxins for which there is no more specific heading, like those from poisonous FISHES. Marine Biotoxins,Phycotoxins
D008839 Microelectrodes Electrodes with an extremely small tip, used in a voltage clamp or other apparatus to stimulate or record bioelectric potentials of single cells intracellularly or extracellularly. (Dorland, 28th ed) Electrodes, Miniaturized,Electrode, Miniaturized,Microelectrode,Miniaturized Electrode,Miniaturized Electrodes
D009991 Oscillometry The measurement of frequency or oscillation changes. Oscillometries
D010080 Oxazoles Five-membered heterocyclic ring structures containing an oxygen in the 1-position and a nitrogen in the 3-position, in distinction from ISOXAZOLES where they are at the 1,2 positions. Oxazole,1,3-Oxazolium-5-Oxides,Munchnones,1,3 Oxazolium 5 Oxides
D010903 Pituitary Gland, Anterior The anterior glandular lobe of the pituitary gland, also known as the adenohypophysis. It secretes the ADENOHYPOPHYSEAL HORMONES that regulate vital functions such as GROWTH; METABOLISM; and REPRODUCTION. Adenohypophysis,Anterior Lobe of Pituitary,Anterior Pituitary Gland,Lobus Anterior,Pars Distalis of Pituitary,Adenohypophyses,Anterior Pituitary Glands,Anterior, Lobus,Anteriors, Lobus,Lobus Anteriors,Pituitary Anterior Lobe,Pituitary Glands, Anterior,Pituitary Pars Distalis
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
D004988 Ethers, Cyclic Compounds of the general formula R-O-R arranged in a ring or crown formation. Cyclic Ether,Cyclic Ethers,Ether, Cyclic
D000200 Action Potentials Abrupt changes in the membrane potential that sweep along the CELL MEMBRANE of excitable cells in response to excitation stimuli. Spike Potentials,Nerve Impulses,Action Potential,Impulse, Nerve,Impulses, Nerve,Nerve Impulse,Potential, Action,Potential, Spike,Potentials, Action,Potentials, Spike,Spike Potential
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

Related Publications

L M Delgado, and P de la Peña, and D del Camino, and F Barros
March 1980, Endocrinology,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
July 1995, Neuroreport,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
February 1994, Pflugers Archiv : European journal of physiology,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
December 1997, Pflugers Archiv : European journal of physiology,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
April 1992, The Biochemical journal,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
March 1995, The EMBO journal,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
August 1992, The Journal of biological chemistry,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
January 1985, The Journal of biological chemistry,
L M Delgado, and P de la Peña, and D del Camino, and F Barros
December 1995, The Journal of endocrinology,
Copied contents to your clipboard!