Biomaterial Database

Neuropeptide Y2 receptors inhibit the frequency of spontaneous but not miniature EPSCs in CA3 pyramidal cells of rat hippocampus. 1996

A R McQuiston, and W F Colmers

Department of Pharmacology, University of Alberta, Edmonton, Canada.

1. Neuropeptide Y (NPY) inhibits synaptic excitation in hippocampal area CA3. We studied its site of action with the use of whole cell patch-clamp recordings from CA3 pyramidal cells of rat hippocampal slices in vitro. 2. Spontaneous excitatory postsynaptic currents (sEPSCs) were isolated with picrotoxin, to block gamma-aminobutyric acid-A receptors, whereas miniature excitatory postsynaptic currents (mEPSCs) were isolated by additionally treating the slice with tetrodotoxin (TTX) and/or Cd2+, sEPSCs and mEPSCs were eliminated by the excitatory amino acid antagonists 6-cyano-7-nitroquinoxaline-2,3-dione (10 microM) and DL-2-amino-5-phosphonovaleric acid (50 microM), and were thus solely attributable to glutamate release. 3. The interval and amplitude distributions of sEPSCS and (TTX-isolated) mEPSCS were analyzed. Either NPY or the rapidly reversible, Y2-receptor-selective agonist [6-aminohexanoic5-24] NPY, ([ahx5-24]NPY) sharply increased the inter-sEPSC intervals in 16 of 16 neurons tested. In 11 of these cells, these agonists also simultaneously shifted the sEPSC amplitude distribution to somewhat smaller amplitudes, whereas in the remaining 5 cells, no concurrent effect on amplitudes was observed. By contrast, in 15 separate neurons treated with 1 microM TTX, neither NPY nor [ahx5-24]NPY altered either mEPSC amplitude or interval distributions of the mEPSCs. 4. To directly compare the effects of Y2 receptor activation on sEPSC and mEPSC properties, we applied [ahx5-24]NPY to the same cell in the absence and presence of TTX (n = 7). sEPSC intervals were characteristically increased by the Y2 agonist in all cells; in six of seven cells the sEPSC distribution was also shifted to smaller amplitudes. TTX application reduced the mean amplitude of the synaptic events more than did [ahx5-24]NPY, while increasing their intervals. [ahx5-24]NPY had no effect in TTX. 5. NPY, acting on a Y2 receptor, inhibits impulse-dependent synaptic excitation of CA3 pyramidal cells of the rat hippocampus by an entirely presynaptic action.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009435	Synaptic Transmission	The communication from a NEURON to a target (neuron, muscle, or secretory cell) across a SYNAPSE. In chemical synaptic transmission, the presynaptic neuron releases a NEUROTRANSMITTER that diffuses across the synaptic cleft and binds to specific synaptic receptors, activating them. The activated receptors modulate specific ion channels and/or second-messenger systems in the postsynaptic cell. In electrical synaptic transmission, electrical signals are communicated as an ionic current flow across ELECTRICAL SYNAPSES.	Neural Transmission,Neurotransmission,Transmission, Neural,Transmission, Synaptic
D009478	Neuropeptide Y	A 36-amino acid peptide present in many organs and in many sympathetic noradrenergic neurons. It has vasoconstrictor and natriuretic activity and regulates local blood flow, glandular secretion, and smooth muscle activity. The peptide also stimulates feeding and drinking behavior and influences secretion of pituitary hormones.	Neuropeptide Y-Like Immunoreactive Peptide,Neuropeptide Tyrosine,Neuropeptide Y Like Immunoreactive Peptide,Tyrosine, Neuropeptide
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
D018408	Patch-Clamp Techniques	An electrophysiologic technique for studying cells, cell membranes, and occasionally isolated organelles. All patch-clamp methods rely on a very high-resistance seal between a micropipette and a membrane; the seal is usually attained by gentle suction. The four most common variants include on-cell patch, inside-out patch, outside-out patch, and whole-cell clamp. Patch-clamp methods are commonly used to voltage clamp, that is control the voltage across the membrane and measure current flow, but current-clamp methods, in which the current is controlled and the voltage is measured, are also used.	Patch Clamp Technique,Patch-Clamp Technic,Patch-Clamp Technique,Voltage-Clamp Technic,Voltage-Clamp Technique,Voltage-Clamp Techniques,Whole-Cell Recording,Patch-Clamp Technics,Voltage-Clamp Technics,Clamp Technique, Patch,Clamp Techniques, Patch,Patch Clamp Technic,Patch Clamp Technics,Patch Clamp Techniques,Recording, Whole-Cell,Recordings, Whole-Cell,Technic, Patch-Clamp,Technic, Voltage-Clamp,Technics, Patch-Clamp,Technics, Voltage-Clamp,Technique, Patch Clamp,Technique, Patch-Clamp,Technique, Voltage-Clamp,Techniques, Patch Clamp,Techniques, Patch-Clamp,Techniques, Voltage-Clamp,Voltage Clamp Technic,Voltage Clamp Technics,Voltage Clamp Technique,Voltage Clamp Techniques,Whole Cell Recording,Whole-Cell Recordings
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