Modulation of the 5-hydroxytryptamine4 receptor-mediated response by short-term and long-term administration of corticosterone in rat CA1 hippocampal pyramidal neurons. 1995

S Birnstiel, and S G Beck
Department of Pharmacology, Loyola University Medical Center, Maywood, Illinois, USA.

Corticosterone (CT) treatment decreases the magnitude of the 5-hydroxytryptamine (5-HT)1A receptor-mediated hyperpolarization in rat CA1 hippocampal pyramidal neurons. In the present study, we examined the short- and long-term effects of CT on the functionally excitatory 5-HT4 receptor-mediated decrease in the amplitude of the slow afterhyperpolarization (sAHP) that follows a calcium spike and the concomitant decrease in sAHP half decay time. Rats were adrenalectomized (ADX) 2 weeks before the experiment. Data for concentration-response curves were obtained with sharp electrode current clamp recordings in the CA1 pyramidal cell layer of hippocampal slices. Significant changes were found in the 5-HT4 receptor-mediated decrease in sAHP amplitude. The Emax of the 5-HT4 response was significantly increased in cells from ADX rats when the superfusion medium contained 1 nM CT. Short-term administration of 100 nM CT did not alter the 5-HT4 response. Chronic treatment with low concentrations of CT decreased the Emax of the 5-HT4 response. Treatment with CT concentrations that mimic conditions of chronic stress decreased the Emax of the 5-HT4 response and shifted the EC50 to the right. Based on these results we conclude that the magnitude and the potency of the 5-HT4 receptor-mediated decrease in sAHP amplitude is altered by CT. Because the short- and long-term effects of CT treatment are not the same, the actions of CT are time and concentration dependent. CT modulation of the 5-HT4 response is different from its modulation of the 5-HT1A response.

UI MeSH Term Description Entries
D008297 Male Males
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
D003345 Corticosterone An adrenocortical steroid that has modest but significant activities as a mineralocorticoid and a glucocorticoid. (From Goodman and Gilman's The Pharmacological Basis of Therapeutics, 8th ed, p1437)
D006624 Hippocampus A curved elevation of GRAY MATTER extending the entire length of the floor of the TEMPORAL HORN of the LATERAL VENTRICLE (see also TEMPORAL LOBE). The hippocampus proper, subiculum, and DENTATE GYRUS constitute the hippocampal formation. Sometimes authors include the ENTORHINAL CORTEX in the hippocampal formation. Ammon Horn,Cornu Ammonis,Hippocampal Formation,Subiculum,Ammon's Horn,Hippocampus Proper,Ammons Horn,Formation, Hippocampal,Formations, Hippocampal,Hippocampal Formations,Hippocampus Propers,Horn, Ammon,Horn, Ammon's,Proper, Hippocampus,Propers, Hippocampus,Subiculums
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
D017207 Rats, Sprague-Dawley A strain of albino rat used widely for experimental purposes because of its calmness and ease of handling. It was developed by the Sprague-Dawley Animal Company. Holtzman Rat,Rats, Holtzman,Sprague-Dawley Rat,Rats, Sprague Dawley,Holtzman Rats,Rat, Holtzman,Rat, Sprague-Dawley,Sprague Dawley Rat,Sprague Dawley Rats,Sprague-Dawley Rats
D051381 Rats The common name for the genus Rattus. Rattus,Rats, Laboratory,Rats, Norway,Rattus norvegicus,Laboratory Rat,Laboratory Rats,Norway Rat,Norway Rats,Rat,Rat, Laboratory,Rat, Norway,norvegicus, Rattus
D017966 Pyramidal Cells Projection neurons in the CEREBRAL CORTEX and the HIPPOCAMPUS. Pyramidal cells have a pyramid-shaped soma with the apex and an apical dendrite pointed toward the pial surface and other dendrites and an axon emerging from the base. The axons may have local collaterals but also project outside their cortical region. Pyramidal Neurons,Cell, Pyramidal,Cells, Pyramidal,Neuron, Pyramidal,Neurons, Pyramidal,Pyramidal Cell,Pyramidal Neuron
D066298 In Vitro Techniques Methods to study reactions or processes taking place in an artificial environment outside the living organism. In Vitro Test,In Vitro Testing,In Vitro Tests,In Vitro as Topic,In Vitro,In Vitro Technique,In Vitro Testings,Technique, In Vitro,Techniques, In Vitro,Test, In Vitro,Testing, In Vitro,Testings, In Vitro,Tests, In Vitro,Vitro Testing, In

Related Publications

S Birnstiel, and S G Beck
January 1996, Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology,
S Birnstiel, and S G Beck
June 2003, Journal of neurophysiology,
S Birnstiel, and S G Beck
July 1994, Pflugers Archiv : European journal of physiology,
S Birnstiel, and S G Beck
October 2000, Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology,
Copied contents to your clipboard!