Biomaterial Database

Spontaneous GABAergic postsynaptic currents in Cajal-Retzius cells in neonatal rat cerebral cortex. 2001

W Kilb, and H J Luhmann

Institut für Neurophysiologie, Heinrich-Heine-Universität Düsseldorf, Postfach 101007, D-40001 Düsseldorf, Germany. kilb@uni-duesseldorf.de

Cajal-Retzius cells are among the first neurons appearing during corticogenesis, and play an important role in the establishment of cortical lamination. The variety of neurotransmitter receptors recently found on these cells imply that they are integrated in the neonatal cortical network. To investigate the presence and properties of spontaneous synaptic activity we performed whole-cell patch-clamp recordings from visually identified and biocytin-labelled Cajal-Retzius cells in a tangential slice preparation of neonatal rat cerebral cortex (postnatal days P0-P5). Spontaneous postsynaptic currents (sPSCs) could be observed in about 23% of the cells using a pipette solution containing 136 m M Cl-. The sPSCs occurred at a low frequency (0.07 +/- 0.07 Hz, n = 42 cells), had an average amplitude of 24.3 +/- 12.4 pA (n = 415 events) and could not be divided in subpopulations according to their amplitude distribution or kinetic properties. The sPSCs were blocked by the GABAA antagonist bicuculline (100 microM), while the glutamatergic antagonists (+/-)-2-amino-5-phosphonopentatonic acid (APV, 30 microM) and 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX, 10 microM), as well as tetrodotoxin (1-2 microM), a blocker of voltage-gated sodium-currents, had no significant effect on sPSCs. The incidence rate of sPSCs declined within the age of the rats and no sPSCs could be observed after P4. These results suggest that Cajal-Retzius cells transiently receive action potential-independent and GABA(A) receptor-mediated spontaneous synaptic input, which may contribute to the refinement of cortical circuits.

UI	MeSH Term	Description	Entries
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
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
D002540	Cerebral Cortex	The thin layer of GRAY MATTER on the surface of the CEREBRAL HEMISPHERES that develops from the TELENCEPHALON and folds into gyri and sulci. It reaches its highest development in humans and is responsible for intellectual faculties and higher mental functions.	Allocortex,Archipallium,Cortex Cerebri,Cortical Plate,Paleocortex,Periallocortex,Allocortices,Archipalliums,Cerebral Cortices,Cortex Cerebrus,Cortex, Cerebral,Cortical Plates,Paleocortices,Periallocortices,Plate, Cortical
D005680	gamma-Aminobutyric Acid	The most common inhibitory neurotransmitter in the central nervous system.	4-Aminobutyric Acid,GABA,4-Aminobutanoic Acid,Aminalon,Aminalone,Gammalon,Lithium GABA,gamma-Aminobutyric Acid, Calcium Salt (2:1),gamma-Aminobutyric Acid, Hydrochloride,gamma-Aminobutyric Acid, Monolithium Salt,gamma-Aminobutyric Acid, Monosodium Salt,gamma-Aminobutyric Acid, Zinc Salt (2:1),4 Aminobutanoic Acid,4 Aminobutyric Acid,Acid, Hydrochloride gamma-Aminobutyric,GABA, Lithium,Hydrochloride gamma-Aminobutyric Acid,gamma Aminobutyric Acid,gamma Aminobutyric Acid, Hydrochloride,gamma Aminobutyric Acid, Monolithium Salt,gamma Aminobutyric Acid, Monosodium Salt
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
D000831	Animals, Newborn	Refers to animals in the period of time just after birth.	Animals, Neonatal,Animal, Neonatal,Animal, Newborn,Neonatal Animal,Neonatal Animals,Newborn Animal,Newborn Animals
D001640	Bicuculline	An isoquinoline alkaloid obtained from Dicentra cucullaria and other plants. It is a competitive antagonist for GABA-A receptors.	6-(5,6,7,8-Tetrahydro-6-methyl-1,3-dioxolo(4,5-g)isoquinolin-5-yl)furo(3,4-e)1,3-benzodioxol-8(6H)one
D013779	Tetrodotoxin	An aminoperhydroquinazoline poison found mainly in the liver and ovaries of fishes in the order TETRAODONTIFORMES, which are eaten. The toxin causes paresthesia and paralysis through interference with neuromuscular conduction.	Fugu Toxin,Tarichatoxin,Tetradotoxin,Toxin, Fugu
D015763	2-Amino-5-phosphonovalerate	The D-enantiomer is a potent and specific antagonist of NMDA glutamate receptors (RECEPTORS, N-METHYL-D-ASPARTATE). The L form is inactive at NMDA receptors but may affect the AP4 (2-amino-4-phosphonobutyrate; APB) excitatory amino acid receptors.	2-Amino-5-phosphonopentanoic Acid,2-Amino-5-phosphonovaleric Acid,2-APV,2-Amino-5-phosphonopentanoate,5-Phosphononorvaline,d-APV,dl-APV,2 Amino 5 phosphonopentanoate,2 Amino 5 phosphonopentanoic Acid,2 Amino 5 phosphonovalerate,2 Amino 5 phosphonovaleric Acid,5 Phosphononorvaline