@article{MTMT:2086363, title = {Neuronal diversity and temporal dynamics: the unity of hippocampal circuit operations.}, url = {https://m2.mtmt.hu/api/publication/2086363}, author = {Klausberger, T and Somogyi, Péter Pál}, doi = {10.1126/science.1149381}, journal-iso = {SCIENCE}, journal = {SCIENCE}, volume = {321}, unique-id = {2086363}, issn = {0036-8075}, abstract = {In the cerebral cortex, diverse types of neurons form intricate circuits and cooperate in time for the processing and storage of information. Recent advances reveal a spatiotemporal division of labor in cortical circuits, as exemplified in the CA1 hippocampal area. In particular, distinct GABAergic (gamma- aminobutyric acid-releasing) cell types subdivide the surface of pyramidal cells and act in discrete time windows, either on the same or on different subcellular compartments. They also interact with glutamatergic pyramidal cell inputs in a domain- specific manner and support synaptic temporal dynamics, network oscillations, selection of cell assemblies, and the implementation of brain states. The spatiotemporal specializations in cortical circuits reveal that cellular diversity and temporal dynamics coemerged during evolution, providing a basis for cognitive behavior.}, keywords = {Animals; Humans; Neurons/*physiology; Nerve Net/*physiology; Hippocampus/cytology/*physiology; Pyramidal Cells/*physiology; Synapses/physiology; cognition; Neural Pathways/physiology; Axons/physiology; gamma-Aminobutyric Acid/metabolism; Dendrites/physiology; Interneurons/*physiology; Biological Evolution}, year = {2008}, eissn = {1095-9203}, pages = {53-57} } @article{MTMT:109665, title = {Perturbed chloride homeostasis and GABAergic signaling in human temporal lobe epilepsy}, url = {https://m2.mtmt.hu/api/publication/109665}, author = {Huberfeld, G and Wittner, Lucia and Clemanceau, S and Baulac, M and Kaila, K and Miles, R and Rivera, C}, doi = {10.1523/JNEUROSCI.2761-07.2007}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {27}, unique-id = {109665}, issn = {0270-6474}, year = {2007}, eissn = {1529-2401}, pages = {9866-9873}, orcid-numbers = {Wittner, Lucia/0000-0001-6800-0953} } @article{MTMT:2833489, title = {Presynaptic, activity-dependent modulation of cannabinoid type 1 receptor-mediated inhibition of GABA release}, url = {https://m2.mtmt.hu/api/publication/2833489}, author = {Földy, Csaba and Neu, A and Jones, MV and Soltesz, Ivan}, doi = {10.1523/JNEUROSCI.4587-05.2006}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {26}, unique-id = {2833489}, issn = {0270-6474}, abstract = {Endocannabinoid signaling couples activity-dependent rises in postsynaptic Ca2+ levels to decreased presynaptic GABA release. Here, we present evidence from paired recording experiments that cannabinoid-mediated inhibition of GABA release depends on the firing rates of the presynaptic interneurons. Low-frequency action potentials in post hoc identified cholecystokinin-positive CA1 basket cells elicited IPSCs in the postsynaptic pyramidal cells that, as expected, were fully abolished by the exogenous application of the cannabinoid receptor agonist WIN55,212-2 [R-(+)-(2,3-dihydro-5-methyl-3-[(4-morpholinyl) methyl]pyrol[1,2,3-de]-1,4-benzoxazin-6-yl)(1-naphthalenyl) methanone monomethanesulfonate] at 5 μM. However, the presynaptic basket cells recovered from the cannabinoid agonist-induced inhibition of GABA release when the presynaptic firing rate was increased to ≥20 Hz. Pharmacological experiments showed that the recovered transmission was exclusively dependent on presynaptic N-type Ca2+ channels. Furthermore, the increased presynaptic firing could also overcome even complete depolarization-induced suppression of inhibition, indicating that the magnitude of DSI markedly depends on the activity levels of basket cells. These results reveal a new locus of activity-dependent modulation for endocannabinoid signaling and suggest that endocannabinoid-mediated inhibition of GABA release may differ in distinct behavioral states. Copyright © 2006 Society for Neuroscience.}, keywords = {Animals; GAMMA-AMINOBUTYRIC ACID; hippocampus; RATS; ARTICLE; CANNABINOIDS; Rats, Sprague-Dawley; priority journal; controlled study; CHOLECYSTOKININ; GABA; nonhuman; animal tissue; animal cell; Neural Inhibition; PLASTICITY; PYRAMIDAL CELLS; Presynaptic Terminals; Naphthalenes; synaptic transmission; Evoked Potentials; Action Potentials; action potential; synapse; neurotransmission; Morpholines; Patch-Clamp Techniques; 4 aminobutyric acid; pyramidal nerve cell; interneuron; Receptor, Cannabinoid, CB1; cannabinoid 1 receptor; cannabinoid; cell membrane depolarization; cell activity; Calcium Channels, N-Type; Neuronal Plasticity; inhibitory postsynaptic potential; 4 aminobutyric acid release; cannabinoid receptor agonist; 2,3 dihydro 5 methyl 3 (morpholinomethyl) 6 (1 naphthoyl)pyrrolo[1,2,3 de][1,4]benzoxazine; calcium channel N type; Paired recording; IPSC; rat; interneurons}, year = {2006}, eissn = {1529-2401}, pages = {1465-1469} } @article{MTMT:1316696, title = {Excitatory effect of GABAergic axo-axonic cells in cortical microcircuits}, url = {https://m2.mtmt.hu/api/publication/1316696}, author = {Szabadics, János and Varga, Csaba and Molnár, Gábor and Oláh, Szabolcs and Barzó, Pál and Tamás, Gábor}, doi = {10.1126/science.1121325}, journal-iso = {SCIENCE}, journal = {SCIENCE}, volume = {311}, unique-id = {1316696}, issn = {0036-8075}, abstract = {Axons in the cerebral cortex receive synaptic input at the axon initial segment almost exclusively from gamma-aminobutyric acid-releasing (GABAergic) axo-axonic cells (AACs). The axon has the lowest threshold for action potential generation in neurons; thus, AACs are considered to be strategically placed inhibitory neurons controlling neuronal output. However, we found that AACs can depolarize pyramidal cells and can initiate stereotyped series of synaptic events in rat and human cortical networks because of a depolarized reversal potential for axonal relative to perisomatic GABAergic inputs. Excitation and signal propagation initiated by AACs is supported by the absence of the potassium chloride cotransporter 2 in the axon.}, year = {2006}, eissn = {1095-9203}, pages = {233-235}, orcid-numbers = {Szabadics, János/0000-0002-4968-2562; Barzó, Pál/0000-0001-8717-748X; Tamás, Gábor/0000-0002-7905-6001} } @article{MTMT:109599, title = {Impaired and repaired inhibitory circuits in the epileptic human hippocampus}, url = {https://m2.mtmt.hu/api/publication/109599}, author = {Maglóczky, Zsófia and Freund, Tamás}, doi = {10.1016/j.tins.2005.04.002}, journal-iso = {TRENDS NEUROSCI}, journal = {TRENDS IN NEUROSCIENCES}, volume = {28}, unique-id = {109599}, issn = {0166-2236}, year = {2005}, eissn = {1878-108X}, pages = {334-340} } @article{MTMT:109379, title = {Surviving CA1 pyramidal cells receive intact perisomatic inhibitory input in the human epileptic hippocampus}, url = {https://m2.mtmt.hu/api/publication/109379}, author = {Wittner, Lucia and Erőss, Loránd and Czirják, Sándor and Halász, Péter and Freund, Tamás and Maglóczky, Zsófia}, doi = {10.1093/brain/awh339}, journal-iso = {BRAIN}, journal = {BRAIN}, volume = {128}, unique-id = {109379}, issn = {0006-8950}, year = {2005}, eissn = {1460-2156}, pages = {138-152}, orcid-numbers = {Wittner, Lucia/0000-0001-6800-0953; Erőss, Loránd/0000-0002-5796-5546; Czirják, Sándor/0000-0002-8224-3561} } @article{MTMT:109314, title = {Interneuron diversity series: Rhythm and mood in perisomatic inhibition}, url = {https://m2.mtmt.hu/api/publication/109314}, author = {Freund, Tamás}, doi = {10.1016/S0166-2236(03)00227-3}, journal-iso = {TRENDS NEUROSCI}, journal = {TRENDS IN NEUROSCIENCES}, volume = {26}, unique-id = {109314}, issn = {0166-2236}, year = {2003}, eissn = {1878-108X}, pages = {489-495} } @article{MTMT:109048, title = {Total number and distribution of inhibitory and excitatory synapses on hippocampal CA1 pyramidal cells}, url = {https://m2.mtmt.hu/api/publication/109048}, author = {Megías, M and Emri, Zsuzsa and Freund, Tamás and Gulyás, Attila}, doi = {10.1016/S0306-4522(00)00496-6}, journal-iso = {NEUROSCIENCE}, journal = {NEUROSCIENCE}, volume = {102}, unique-id = {109048}, issn = {0306-4522}, year = {2001}, eissn = {1873-7544}, pages = {527-540}, orcid-numbers = {Gulyás, Attila/0000-0003-4961-636X} } @article{MTMT:109558, title = {The apical shaft of CA1 pyramidal cells is under GABAergic interneuronal control}, url = {https://m2.mtmt.hu/api/publication/109558}, author = {Papp, Edit and Leinekugel, X and Henze, DA and Lee, J and Buzsáki, György}, doi = {10.1016/S0306-4522(00)00584-4}, journal-iso = {NEUROSCIENCE}, journal = {NEUROSCIENCE}, volume = {102}, unique-id = {109558}, issn = {0306-4522}, year = {2001}, eissn = {1873-7544}, pages = {715-721} } @article{MTMT:2138095, title = {Cell surface domain specific postsynaptic currents evoked by identified GABAergic neurones in rat hippocampus in vitro.}, url = {https://m2.mtmt.hu/api/publication/2138095}, author = {Maccaferri, G and Roberts, JD and Szűcs, Péter and Cottingham, CA and Somogyi, Péter Pál}, doi = {10.1111/j.1469-7793.2000.t01-3-00091.x}, journal-iso = {J PHYSIOL-LONDON}, journal = {JOURNAL OF PHYSIOLOGY-LONDON}, volume = {524}, unique-id = {2138095}, issn = {0022-3751}, abstract = {1. Inhibitory postsynaptic currents (IPSCs) evoked in CA1 pyramidal cells (n = 46) by identified interneurones (n = 43) located in str. oriens were recorded in order to compare their functional properties and to determine the effect of synapse location on the apparent IPSC kinetics as recorded using somatic voltage clamp at -70 mV and nearly symmetrical [Cl-]. 2. Five types of visualised presynaptic interneurone, oriens-lacunosum moleculare (O-LMC), basket (BC), axo-axonic (AAC), bistratified (BiC) and oriens-bistratified (O-BiC) cells, were distinguished by immunocytochemistry and/or synapse location using light and electron microscopy. 3. Somatostatin immunoreactive O-LMCs, innervating the most distal dendritic shafts and spines, evoked the smallest amplitude (26 +/- 10 pA, s.e.m., n = 8) and slowest IPSCs (10-90 % rise time, 6.2 +/- 0.6 ms; decay, 20.8 +/- 1.7 ms, n = 8), with no paired-pulse modulation of the second IPSC (93 +/- 4 %) at 100 ms interspike interval. In contrast, parvalbumin-positive AACs evoked larger amplitude (308 +/- 103 pA, n = 7) and kinetically faster (rise time, 0.8 +/- 0.1 ms; decay 11.2 +/- 0.9 ms, n = 7) IPSCs showing paired-pulse depression (to 68 +/- 5 %, n = 6). Parvalbumin- or CCK-positive BCs (n = 9) terminating on soma/dendrites, BiCs (n = 4) and O-BiCs (n = 7) innervating dendrites evoked IPSCs with intermediate kinetic parameters. The properties of IPSCs and sensitivity to bicuculline indicated that they were mediated by GABAA receptors. 4. In three cases, kinetically complex, multiphasic IPSCs, evoked by an action potential in the recorded basket cells, suggested that coupled interneurones, possibly through electrotonic junctions, converged on the same postsynaptic neurone. 5. The population of O-BiCs (4 of 4 somatostatin positive) characterised in this study had horizontal dendrites restricted to str. oriens/alveus and innervated stratum radiatum and oriens. Other BiCs had radial dendrites as described earlier. The parameters of IPSCs evoked by BiCs and O-BiCs showed the largest cell to cell variation, and a single interneurone could evoke both small and slow as well as large and relatively fast IPSCs. 6. The kinetic properties of the somatically recorded postsynaptic current are correlated with the innervated cell surface domain. A significant correlation of rise and decay times for the overall population of unitary IPSCs suggests that electrotonic filtering of distal responses is a major factor for the location and cell type specific differences of unitary IPSCs, but molecular heterogeneity of postsynaptic GABAA receptors may also contribute to the observed kinetic differences. Furthermore, domain specific differences in the short-term plasticity of the postsynaptic response indicate a differentiation of interneurones in activity-dependent responses.}, keywords = {Animals; RATS; KINETICS; Parvalbumins/analysis; Synaptic Transmission/*physiology; gamma-Aminobutyric Acid/*physiology; Rats, Wistar; Cell Membrane/physiology; Excitatory Postsynaptic Potentials/*physiology; Neurons/cytology/*physiology; Hippocampus/*physiology; Receptors, GABA-A/physiology; Patch-Clamp Techniques; Bicuculline/pharmacology; Synapses/*physiology/ultrastructure; Somatostatin/analysis; Axons/physiology/ultrastructure; Dendrites/physiology/ultrastructure; Cholecystokinin/pharmacology; Interneurons/cytology/physiology}, year = {2000}, eissn = {1469-7793}, pages = {91-116}, orcid-numbers = {Szűcs, Péter/0000-0003-4635-6427} } @article{MTMT:2138098, title = {Target-cell-specific facilitation and depression in neocortical circuits.}, url = {https://m2.mtmt.hu/api/publication/2138098}, author = {Reyes, A and Lujan, R and Rozov, A and Burnashev, N and Somogyi, Péter Pál and Sakmann, B}, journal-iso = {NAT NEUROSCI}, journal = {NATURE NEUROSCIENCE}, volume = {1}, unique-id = {2138098}, issn = {1097-6256}, abstract = {In neocortical circuits, repetitively active neurons evoke unitary postsynaptic potentials (PSPs) whose peak amplitudes either increase (facilitate) or decrease (depress) progressively. To examine the basis for these different synaptic responses, we made simultaneous recordings from three classes of neurons in cortical layer 2/3. We induced repetitive action potentials in pyramidal cells and recorded the evoked unitary excitatory (E)PSPs in two classes of GABAergic neurons. We observed facilitation of EPSPs in bitufted GABAergic interneurons, many of which expressed somatostatin immunoreactivity. EPSPs recorded from multipolar interneurons, however, showed depression. Some of these neurons were immunopositive for parvalbumin. Unitary inhibitory (I)PSPs evoked by repetitive stimulation of a bitufted neuron also showed a less pronounced but significant difference between the two target neurons. Facilitation and depression involve presynaptic mechanisms, and because a single neuron can express both behaviors simultaneously, we infer that local differences in the molecular structure of presynaptic nerve terminals are induced by retrograde signals from different classes of target neurons. Because bitufted and multipolar neurons both formed reciprocal inhibitory connections with pyramidal cells, the results imply that the balance of activation between two recurrent inhibitory pathways in the neocortex depends on the frequency of action potentials in pyramidal cells.}, keywords = {Animals; RATS; Excitatory Postsynaptic Potentials/physiology; Pyramidal Cells/physiology; Electric Stimulation; Neural Pathways/cytology/physiology; Action Potentials/physiology; Synapses/physiology; Electrophysiology; Neural Inhibition/physiology; gamma-Aminobutyric Acid/physiology; Neocortex/cytology/*physiology; Neurons/physiology; Somatostatin/metabolism; Interneurons/metabolism/physiology}, year = {1998}, eissn = {1546-1726}, pages = {279-285} } @article{MTMT:2966613, title = {Long-lasting GABA-mediated depolarization evoked by high-frequency stimulation in pyramidal neurons of rat hippocampal slice is attributable to a network-driven, bicarbonate-dependent K+ transient.}, url = {https://m2.mtmt.hu/api/publication/2966613}, author = {Kaila, K and Lamsa, Karri and Smirnov, S and Taira, T and Voipio, J}, journal-iso = {J NEUROSCI}, journal = {JOURNAL OF NEUROSCIENCE}, volume = {17}, unique-id = {2966613}, issn = {0270-6474}, abstract = {Biphasic GABAA-mediated postsynaptic responses can be readily evoked in CA1 pyramidal neurons of rat hippocampal slices by high-frequency stimulus (HFS) trains in the presence of ionotropic glutamate receptor antagonists. In the present experiments with sharp microelectrodes, whole-cell techniques, and K+-selective microelectrodes, an HFS train (40 pulses at 100 Hz) applied in stratum radiatum close to the recording site evoked a brief hyperpolarizing IPSP (hIPSP), which turned into a prolonged (2-3 sec) depolarization (GABA-mediated depolarizing postsynaptic potential; GDPSP). The I-V relationships of the postsynaptic currents (hIPSC and GDPSC) had distinct characteristics: the hIPSC and the early GDPSC showed outward rectification, whereas the late GDPSC was reduced with positive voltage steps to zero or beyond (inward rectification), but often no clear reversal was seen. That two distinct currents contribute to the generation of the GDPSP was also evident from the finding that a second HFS train at peak or late GDPSP induced a prompt GABAA-mediated hyperpolarization. The GDPSP/C was dependent on the availability of bicarbonate, but not on interstitial or intrapyramidal carbonic anhydrase activity. The HFS train evoked a rapid GABAA-mediated bicarbonate-dependent increase in the extracellular K+ concentration ([K+]o), and the GDPSP followed the K+ transient in a sub-Nernstian manner. The spatial and pharmacological characteristics of the [K+]o shift indicated that it is generated by a local network of GABAergic interneurons. The brief ascending phase of the GDPSP is linked to a K+-dependent accumulation of intracellular Cl-. Thereafter, a nonsynaptic mechanism, a direct depolarizing effect of the [K+]o shift, is responsible for the most conspicuous characteristics of the GDPSP: its large amplitude and prolonged duration.}, keywords = {Animals; Male; RATS; Nerve Net/*physiology; Hippocampus/cytology/*physiology; Pyramidal Cells/*physiology; Synapses/physiology; Electrophysiology; gamma-Aminobutyric Acid/*physiology; Time Factors; synaptic transmission; electric conductivity; Rats, Wistar; Potassium/*metabolism; Culture Media; Electric Stimulation/methods; Neuroglia/physiology; Carbonic Anhydrase Inhibitors/pharmacology; Bicarbonates/*metabolism; In Vitro Techniques}, year = {1997}, eissn = {1529-2401}, pages = {7662-7672}, orcid-numbers = {Lamsa, Karri/0000-0002-4609-1337} } @article{MTMT:107931, title = {Interneurons of the hippocampus}, url = {https://m2.mtmt.hu/api/publication/107931}, author = {Freund, Tamás and Buzsáki, György}, doi = {10.1002/(SICI)1098-1063(1996)6:4<347::AID-HIPO1>3.0.CO;2-I}, journal-iso = {HIPPOCAMPUS}, journal = {HIPPOCAMPUS}, volume = {6}, unique-id = {107931}, issn = {1050-9631}, year = {1996}, eissn = {1098-1063}, pages = {347-470} } @article{MTMT:107721, title = {Differences between somatic and dendritic inhibition in the hippocampus}, url = {https://m2.mtmt.hu/api/publication/107721}, author = {Miles, R and Tóth, Katalin and Gulyás, Attila and Hájos, Norbert and Freund, Tamás}, doi = {10.1016/S0896-6273(00)80101-4}, journal-iso = {NEURON}, journal = {NEURON}, volume = {16}, unique-id = {107721}, issn = {0896-6273}, year = {1996}, eissn = {1097-4199}, pages = {815-823}, orcid-numbers = {Gulyás, Attila/0000-0003-4961-636X} } @article{MTMT:1661000, title = {SYNCHRONIZATION OF NEURONAL-ACTIVITY IN HIPPOCAMPUS BY INDIVIDUAL GABAERGIC INTERNEURONS}, url = {https://m2.mtmt.hu/api/publication/1661000}, author = {COBB, SR and BUHL, EH and Halasy, Katalin and PAULSEN, O and Somogyi, Péter Pál}, doi = {10.1038/378075a0}, journal-iso = {NATURE}, journal = {NATURE}, volume = {378}, unique-id = {1661000}, issn = {0028-0836}, abstract = {SYNCHRONIZATION Of neuronal activity is fundamental in the operation of cortical networks(1). With respect to an ongoing synchronized oscillation, the precise timing of action potentials is an attractive candidate mechanism for information coding(2-5) Networks of inhibitory interneurons have been proposed to have a role in entraining cortical, synchronized 40-Hz activity(6,7). Here we demonstrate that individual GABAergic interneurons(8) can effectively phase spontaneous firing and subthreshold oscillations in hippocampal pyramidal cells at theta frequencies (4-7 Hz). The efficiency of this entrainment is due to interaction of GABA(A)-receptor-mediated hyperpolarizing synaptic events with intrinsic oscillatory mechanisms tuned to this frequency range in pyramidal cells. Moreover, this GABAergic mechanism is sufficient to synchronize the firing of pyramidal cells. Thus, owing to the divergence of each GABAergic interneuron(9,10), more than a thousand pyramidal cells may share a common temporal reference established by an individual interneuron.}, year = {1995}, eissn = {1476-4687}, pages = {75-78} } @article{MTMT:1660995, title = {DIVERSE SOURCES OF HIPPOCAMPAL UNITARY INHIBITORY POSTSYNAPTIC POTENTIALS AND THE NUMBER OF SYNAPTIC RELEASE SITES}, url = {https://m2.mtmt.hu/api/publication/1660995}, author = {BUHL, EH and Halasy, Katalin and Somogyi, Péter Pál}, doi = {10.1038/368823a0}, journal-iso = {NATURE}, journal = {NATURE}, volume = {368}, unique-id = {1660995}, issn = {0028-0836}, abstract = {Dual intracellular recordings from microscopically identified neurons in the hippocampus reveal that the synaptic terminals of three morphologically distinct types of interneuron act through GABA(A) receptors. Each type of interneuron forms up to 12 synaptic contacts with a postsynaptic principal neuron, but each interneuron innervates a different domain of the surface of the postsynaptic neuron. Different kinetics of the postsynaptic effects, together with the strategic placement of synapses, indicate that these GABAergic interneurons serve distinct functions in the cortical network.}, year = {1994}, eissn = {1476-4687}, pages = {823-828} } @article{MTMT:107599, title = {Precision and variability in postsynaptic target selection of inhibitory cells in the hippocampal CA3 region}, url = {https://m2.mtmt.hu/api/publication/107599}, author = {Gulyás, Attila and Miles, R and Hájos, Norbert and Freund, Tamás}, doi = {10.1111/j.1460-9568.1993.tb00240.x}, journal-iso = {EUR J NEUROSCI}, journal = {EUROPEAN JOURNAL OF NEUROSCIENCE}, volume = {5}, unique-id = {107599}, issn = {0953-816X}, year = {1993}, eissn = {1460-9568}, pages = {1729-1751}, orcid-numbers = {Gulyás, Attila/0000-0003-4961-636X} } @article{MTMT:2138105, title = {A high degree of spatial selectivity in the axonal and dendritic domains of physiologically identified local-circuit neurons in the dentate gyrus of the rat hippocampus. A High Degree of Spatial Selectivity in the Axonal and Dendritic Domains of Physiologically Identified Local‐circuit Neurons in the Dentate Gyms of the Rat Hippocampus}, url = {https://m2.mtmt.hu/api/publication/2138105}, author = {Han, ZS and Buhl, EH and Lőrinczi, Zoltán and Somogyi, Péter Pál}, doi = {10.1111/j.1460-9568.1993.tb00507.x}, journal-iso = {EUR J NEUROSCI}, journal = {EUROPEAN JOURNAL OF NEUROSCIENCE}, volume = {5}, unique-id = {2138105}, issn = {0953-816X}, abstract = {The axonal and dendritic domains of neurons with extensive, locally arborizing axons were delineated in the dentate gyrus of the rat hippocampus. In horizontally cut slice preparations neurons were briefly recorded and subsequently filled with biocytin when one or several of the following physiological properties were observed: (i) high-amplitude short-latency spike afterhyperpolarization; (ii) lack of spike frequency adaptation; (iii) high firing rate in response to depolarizing current. In a sample of 14 neurons, sufficient dendritic and/or axonal detail was recovered to identify them as non-principal cells, i.e. non-granule, non-mossy cells. Five distinct types of cells were recognized, based on the spatial distribution of dendrites, presumably reflecting the availability of afferents, and on the basis of the highly selective distribution of their axon terminals, indicating synaptic target selectivity. They are: (1) the hilar cell forming a dense axonal plexus in the commissural and association pathway terminal field (HICAP cell; horizontal axon extent 1.6 mm) in the inner one-third of the molecular layer, and having dendrites extending from the hilus to the top of the molecular layer; (2) the hilar cell with its axon ramifying in the perforant path terminal field (HIPP cell, horizontal axon extent 2.0 mm) in the outer two-thirds of the molecular layer, whereas its spiny dendrites were restricted to the hilus; (3) the molecular layer cell with its dendritic and axonal domains confined to the perforant path terminal zone (MOPP cell, horizontal extent of axon 2.0 mm); (4) the dentate basket cell (horizontal axon extent 0.9 mm) had most of its axon concentrated in the granule cell layer, the remainder being localized in the inner molecular layer and hilus; (5) the hilar chandelier cell, or axo-axonic cell (horizontal axon extent 1.1 mm), densely innervating the granule cell layer with fascicles of radially oriented terminal rows, and also forming an extensive plexus in the hilus. The three cell types having their somata in the hilus projected to granule cells at the same septo-temporal level where their cell bodies were located. The results demonstrate that there is a spatially selective innervation of the granule cells by at least five distinct types of dentate neurons, which terminate in several instances in mutually exclusive domains. Their dendrites may have access to all (HICAP cell) or only a few (e.g. HIPP and MOPP cell) of the hippocampal afferents. This arrangement provides a framework for independent interaction between the output of local circuit neurons and subsets of excitatory afferents providing input to principal cells.}, keywords = {Animals; Female; RATS; ARTICLE; Neural Pathways; Lysine/analogs & derivatives; priority journal; controlled study; nonhuman; animal tissue; animal cell; spatial orientation; brain electrophysiology; nerve cell membrane potential; cellular distribution; spike; spike wave; action potential; dentate gyrus; brain tissue; Rats, Wistar; synapse; nerve ending; nerve conduction; cell structure; Cell Shape; nerve fiber; sensory nerve cell; interneuron; Axons/*ultrastructure; cell specificity; Dendrites; hyperpolarization; granule cell; brain nerve cell; Interneurons/physiology/ultrastructure; Dendrites/*ultrastructure; nerve fiber growth; Neural Pathways/physiology/ultrastructure; Neurons/*physiology/*ultrastructure; Hippocampus/*physiology/*ultrastructure; Basket cell; axo‐axonic cell; afterdischarge}, year = {1993}, eissn = {1460-9568}, pages = {395-410} }