Biomaterial Database

Histamine phase shifts the hamster circadian pacemaker via an NMDA dependent mechanism. 1998

J L Meyer, and A C Hall, and M E Harrington

Department of Psychology, Smith College, Northampton, MA 01063, USA.

The SCN acts as the central pacemaker for circadian rhythms in mammals. Histamine has been shown to affect circadian rhythms both in vivo and in vitro. We investigated the mechanism by which histamine phase shifts circadian rhythms in vitro. Hypothalamic slices containing the SCN were prepared from golden hamsters, and spontaneous firing rates of individual cells were recorded on the second day in vitro. Application of histamine (1 microM-10 mM) at the extrapolated time of 2 h after lights off (ZT 14) on day 1 in vitro delayed the time of peak firing in a dose-dependent manner. Pre-exposure to the N-methyl-D-aspartate (NMDA) receptor antagonist (+/-)-2-amino-5-phosphonopentanoic acid (AP-5; 100 microM-1 mM) 5 min before histamine (1 microM) was applied to the slice blocked the phase-delaying effects of histamine. Application of the H1 blocker mepryamine (100 nM) or the H2 blocker cimetidine (10 microM) followed by histamine had no effect on the phase delay induced by histamine. In whole cell recordings from acutely dissociated neurons of hamster SCN, histamine (50 microM) was shown to potentiate NMDA-evoked currents by 52 +/- 12%. These experiments demonstrate that histamine phase shifts of the circadian clock are dependent on NMDA receptor activation and that histamine can directly potentiate NMDA currents in SCN neurons. Histamine may alter circadian clock function by acting directly on NMDA receptors, possibly via binding to the polyamine site.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D008647	Mesocricetus	A genus in the order Rodentia and family Cricetidae. One species, Mesocricetus auratus or golden hamster is widely used in biomedical research.	Hamsters, Golden,Hamsters, Golden Syrian,Hamsters, Syrian,Mesocricetus auratus,Syrian Golden Hamster,Syrian Hamster,Golden Hamster,Golden Hamster, Syrian,Golden Hamsters,Golden Syrian Hamsters,Hamster, Golden,Hamster, Syrian,Hamster, Syrian Golden,Syrian Hamsters
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
D010775	Photic Stimulation	Investigative technique commonly used during ELECTROENCEPHALOGRAPHY in which a series of bright light flashes or visual patterns are used to elicit brain activity.	Stimulation, Photic,Visual Stimulation,Photic Stimulations,Stimulation, Visual,Stimulations, Photic,Stimulations, Visual,Visual Stimulations
D002940	Circadian Rhythm	The regular recurrence, in cycles of about 24 hours, of biological processes or activities, such as sensitivity to drugs or environmental and physiological stimuli.	Diurnal Rhythm,Nyctohemeral Rhythm,Twenty-Four Hour Rhythm,Nycthemeral Rhythm,Circadian Rhythms,Diurnal Rhythms,Nycthemeral Rhythms,Nyctohemeral Rhythms,Rhythm, Circadian,Rhythm, Diurnal,Rhythm, Nycthemeral,Rhythm, Nyctohemeral,Rhythm, Twenty-Four Hour,Rhythms, Circadian,Rhythms, Diurnal,Rhythms, Nycthemeral,Rhythms, Nyctohemeral,Rhythms, Twenty-Four Hour,Twenty Four Hour Rhythm,Twenty-Four Hour Rhythms
D006224	Cricetinae	A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.	Cricetus,Hamsters,Hamster
D006632	Histamine	An amine derived by enzymatic decarboxylation of HISTIDINE. It is a powerful stimulant of gastric secretion, a constrictor of bronchial smooth muscle, a vasodilator, and also a centrally acting neurotransmitter.	Ceplene,Histamine Dihydrochloride,Histamine Hydrochloride,Peremin
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
D016194	Receptors, N-Methyl-D-Aspartate	A class of ionotropic glutamate receptors characterized by affinity for N-methyl-D-aspartate. NMDA receptors have an allosteric binding site for glycine which must be occupied for the channel to open efficiently and a site within the channel itself to which magnesium ions bind in a voltage-dependent manner. The positive voltage dependence of channel conductance and the high permeability of the conducting channel to calcium ions (as well as to monovalent cations) are important in excitotoxicity and neuronal plasticity.	N-Methyl-D-Aspartate Receptor,N-Methyl-D-Aspartate Receptors,NMDA Receptor,NMDA Receptor-Ionophore Complex,NMDA Receptors,Receptors, NMDA,N-Methylaspartate Receptors,Receptors, N-Methylaspartate,N Methyl D Aspartate Receptor,N Methyl D Aspartate Receptors,N Methylaspartate Receptors,NMDA Receptor Ionophore Complex,Receptor, N-Methyl-D-Aspartate,Receptor, NMDA,Receptors, N Methyl D Aspartate,Receptors, N Methylaspartate
D016202	N-Methylaspartate	An amino acid that, as the D-isomer, is the defining agonist for the NMDA receptor subtype of glutamate receptors (RECEPTORS, NMDA).	N-Methyl-D-aspartate,NMDA,N-Methyl-D-aspartic Acid,Acid, N-Methyl-D-aspartic,N Methyl D aspartate,N Methyl D aspartic Acid,N Methylaspartate