Biomaterial Database

Inhibitory control of excitable dendrites in neocortex. 1995

H G Kim, and M Beierlein, and B W Connors

Department of Neuroscience, Brown University, Providence, Rhode Island 02912, USA.

1. Many dendrites of pyramidal cells in mature neocortex express active Na+ and Ca2+ conductances. Dendrites are also the target of numerous inhibitory synapses. We examined the interactions between the intrinsic excitability of dendrites and synaptic inhibition using whole cell recordings from the apical dendrites of layer 5 pyramidal cells. Experiments were performed on slices of somatosensory cortex from mature rats. Slices were bathed in the glutamate receptor antagonists 2-amino-5-phosphonopentanoic acid and 6,7-dinitroquinoxaline-2,3-dione, and maintained at 32-36 degrees C. 2. In agreement with previous findings, intradendritic current injection evoked two distinct types of dendritic firing. Type I dendrites generated monophasic fast spikes, whereas type II dendrites showed more complex firing patterns, consisting of fast and slow spike components. 3. Stimulation of cortical layers 2/3 evoked fast inhibitory postsynaptic potentials (IPSPs) in all dendrites tested. IPSP reversal potentials were bimodally distributed, with means of about -53 and -85 mV when recorded with high-Cl(-)-concentration-filled electrodes. Interestingly, IPSP reversal potentials were correlated with the type of dendritic spiking pattern. 4. IPSPs were able to delay, completely block, or partially block spiking in dendrites, depending on the relative timing between inhibition and dendritic spiking. Slow, Ca(2+)-dependent spike components could be blocked selectively by IPSPs. Furthermore, inhibition could either phase advance or phase delay repetitive patterns of dendritic spiking, depending on the timing of the IPSP.

UI	MeSH Term	Description	Entries
D008297	Male		Males
D009433	Neural Inhibition	The function of opposing or restraining the excitation of neurons or their target excitable cells.	Inhibition, Neural
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
D011930	Reaction Time	The time from the onset of a stimulus until a response is observed.	Response Latency,Response Speed,Response Time,Latency, Response,Reaction Times,Response Latencies,Response Times,Speed, Response,Speeds, Response
D003712	Dendrites	Extensions of the nerve cell body. They are short and branched and receive stimuli from other NEURONS.	Dendrite
D004558	Electric Stimulation	Use of electric potential or currents to elicit biological responses.	Stimulation, Electric,Electrical Stimulation,Electric Stimulations,Electrical Stimulations,Stimulation, Electrical,Stimulations, Electric,Stimulations, Electrical
D004594	Electrophysiology	The study of the generation and behavior of electrical charges in living organisms particularly the nervous system and the effects of electricity on living organisms.
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
D013003	Somatosensory Cortex	Area of the parietal lobe concerned with receiving sensations such as movement, pain, pressure, position, temperature, touch, and vibration. It lies posterior to the central sulcus.	Brodmann Area 1,Brodmann Area 2,Brodmann Area 3,Brodmann Areas 1, 2, 3,Brodmann Areas 1, 2, and 3,Brodmann Areas 3, 1, 2,Brodmann Areas 3, 1, and 2,Brodmann's Area 1,Brodmann's Area 2,Brodmann's Area 3,Brodmann's Areas 1, 2, and 3,Brodmann's Areas 3, 1, and 2,Parietal-Opercular Cortex,Primary Somesthetic Area,S1 Cortex,S2 Cortex,SII Cortex,Anterior Parietal Cortex,Gyrus Postcentralis,Post Central Gyrus,Postcentral Gyrus,Primary Somatic Sensory Area,Primary Somatosensory Area,Primary Somatosensory Areas,Primary Somatosensory Cortex,SI Cortex,Second Somatic Sensory Area,Secondary Sensory Cortex,Secondary Somatosensory Area,Secondary Somatosensory Cortex,Area 1, Brodmann,Area 1, Brodmann's,Area 2, Brodmann,Area 2, Brodmann's,Area 3, Brodmann,Area 3, Brodmann's,Area, Primary Somatosensory,Area, Primary Somesthetic,Area, Secondary Somatosensory,Areas, Primary Somatosensory,Brodmanns Area 1,Brodmanns Area 2,Brodmanns Area 3,Cortex, Anterior Parietal,Cortex, Parietal-Opercular,Cortex, Primary Somatosensory,Cortex, S1,Cortex, S2,Cortex, SI,Cortex, SII,Cortex, Secondary Sensory,Cortex, Secondary Somatosensory,Cortex, Somatosensory,Gyrus, Post Central,Gyrus, Postcentral,Parietal Cortex, Anterior,Parietal Opercular Cortex,Parietal-Opercular Cortices,Primary Somatosensory Cortices,Primary Somesthetic Areas,S1 Cortices,S2 Cortices,SII Cortices,Secondary Somatosensory Areas,Sensory Cortex, Secondary,Somatosensory Area, Primary,Somatosensory Area, Secondary,Somatosensory Areas, Primary,Somatosensory Cortex, Primary,Somatosensory Cortex, Secondary,Somesthetic Area, Primary,Somesthetic Areas, Primary
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