Dentate gyrus granule GLU cell

- - HG - DG - PRINC - granule - - dyn
Properties are:  Present   Absent 
Input Receptors
Intrinsic Currents
Output Transmitters
Distal equivalent dendrite
Perforant path terminals NMDA
Perforant path terminals AMPA
Perforant path terminals mGluR
Hilar spiny interneuron terminals GabaA
Hilar spiny interneuron terminals GabaB
I Na,t
I A
I L high threshold
I Na,p
low density
Dynorphin Perforant path terminals
Middle equivalent dendrite
Perforant path terminals AMPA
Perforant path terminals mGluR
Hilar spiny and aspiny interneuron terminals GabaA
Perforant path terminals NMDA
Hilar spiny and aspiny interneuron terminals GabaB
I L high threshold
I Na,p
low density
I Na,t
Indirect experimental evidence for dendritic Na channels was suggested by laminar filed potential studies (Jefferys JG, 197910 ).
Dynorphin Perforant path terminals
Proximal equivalent dendrite
Hilar mossy cell collaterals and commissural cell terminals NMDA
Hilar aspiny interneuron terminals GabaB
Hilar mossy cell collaterals and commissural cell terminals mGluR
Hilar mossy cell collaterals and commissural cell terminals AMPA
Hilar aspiny interneuron terminals GabaA
I L high threshold
I Na,p
I Na,t
Indirect experimental evidence for dendritic Na channels was suggested by laminar filed potential studies (Jefferys JG, 197910 ).
Soma
Basket cell terminals GabaB
Basket cell terminals GabaA
Whole cell and perforated patch recordings in slices showed bicuculline-dependent and ?independent GABA currents from juvenile rats, suggesting two types of GABAergic inputs. The bicuculline-independent component was present only at the earliest stages of maturation, had a later peak, slower time course of decay, and marked outward rectification. A trophic or signaling role rather than primarily inhibitory was suggested for this current (Liu YB et al, 1998 [rat]1 ).
AMPA
NMDA and AMPA conductances properties were studied using patch-clamp recordings in morphologically identified cells in slices prepared from surgically removed medial temporal lobe specimens of epileptic patients (14 specimens from 14 patients (Isokawa M et al, 1997 [human]2 ).
NMDA
NMDA and AMPA conductances properties were studied using patch-clamp recordings in morphologically identified cells in slices prepared from surgically removed medial temporal lobe specimens of epileptic patients (14 specimens from 14 patients). The wide range of changes in the slope conductance of the NMDA EPSCs suggests that the NMDA-receptor-mediated conductance could be altered in human epileptic DGCs (Isokawa M et al, 1997 [human]2 ).
Septum principal ACh cell
 -Axon terminal.Acetylcholine
Nicotinic
I K,Ca
Voltage-clamp analysis suggested that IAHP in DG neurones is generated by about 1200 channels, and that about 60% are open at the peak of a maximal IAHP (Valiante TA et al, 1997 [rat]4 ).
I L high threshold
Cells acutely dissociated from slices obtained from chronic temporal lobe epilepsy patients displayed a high-voltage activated Ca2+ conductance with a pronounced Ca2+-dependent inactivation (Nagerl UV and Mody I, 1998 [human]5 ). Patch-clamp recordings from human cells showed N-type, L-type and T-type currents that had similar pharmacological and kinetic characteristics as in control rats. The current density was significantly larger in human and in the kainate model compared to cells isolated from adult control rats (Beck H et al, 1998 [human]6 ).
I N
Patch-clamp recordings from human cells showed N-type, L-type and T-type currents that had similar pharmacological and kinetic characteristics as in control rats. The current density was significantly larger in human and in the kainate model compared to cells isolated from adult control rats (Beck H et al, 1998 [human]6 ).
I T low threshold
Patch-clamp recordings from human cells showed N-type, L-type and T-type currents that had similar pharmacological and kinetic characteristics as in control rats. The current density was significantly larger in human and in the kainate model compared to cells isolated from adult control rats (Beck H et al, 1998 [human]6 ).
I A
Properties of potassium outward currents were investigated from 11 specimens obtained from patients with temporal lobe epilepsy. An IK but not IA or inwardly rectifying potassium currents, were observed in all cells (Beck H et al, 1996 [human]7 ). The properties of outward currents were investigated with patch-clamp in acutely isolated cells at various postnatal ages and at adulthood (2-3 mo). Kinetic analysis and pharmacological properties showed that IK and IA were present in these cells. IA and IK remained stable with respect to kinetic properties during ontogenesis, but the relative contribution and pharmacological properties varied with age. IA dominated in P5-7 cells whereas IK was prominent in most older cells (Beck H et al, 1992 [rat]8 ).
I h
Patch-pipette recordings found no evidence for a ?sag? in hyperpolarizing responses, suggesting that this current is not present in these neurons (Lübke J et al, 19989 ).
I Na,t
With whole-cell recordings the properties of a voltage-dependent Na+ currents were investigated in 42 DGC acutely isolated from the resected hippocampus of 20 patients with therapy-refractory temporal lobe epilepsy (TLE) using the whole-cell patch-clamp technique.The kinetic properties contributed to a reduction of the Na+ currents during repetitive stimulation that was more pronounced with higher stimulation frequencies and also showed a dependence on the holding potential (Reckziegel G et al, 1998 [human]11 ). The kinetic properties of this current were studied using the whole-cell voltage-clamp method in acutely isolated cells. No significant differences were found after induction of status epilepticus (Ketelaars SO et al, 200112 ).
I K
Properties of K+ outward currents were investigated in human DG cells from 11 specimens obtained from patients with temporal lobe epilepsy. An IK was observed in all cells. The average current density, the time-dependent decay, and the resting membrane characteristics were not significantly different between patients with and without Ammon Horn Sclerosis. The V1/2(inact) was shifted in a hyperpolarizing direction in AHS (-67.7mV) compared with that in hippocampi not showing AHS (-47.7mV) (Beck H et al, 1996 [human]7 ). The properties of outward currents were investigated with patch-clamp in acutely isolated rat DGCs at various postnatal ages and at adulthood (2-3 mo). Kinetic analysis and pharmacological properties showed that IK and IA were present in these cells. IA and IK remained stable with respect to kinetic properties during ontogenesis, but the relative contribution and pharmacological properties varied with age. IA dominated in P5-7 cells whereas IK was prominent in most older cells (Beck H et al, 1992 [rat]8 ).
Axon hillock
Chandelier cell terminals GabaA
Chandelier cell terminals GabaB
I K
I Na,t
I K,Ca
Axon fiber
Glutamate To presynaptic kainate receptors in the CA3 region of the hippocampus
Glutamate - kainate receptor (glur6)In mouse hippocampal slices, bath application of kainate caused presynaptic reduction in epscs at mossy fiber synapses on CA3 pyramidal cells in glur6 knockouts but not in glur5 knockouts.(Rockett R, 2010 [mice]14 ).
Axon terminal
Kainate
It has been shown that activation of these receptors could facilitate transmitter release. Their activation is very fast (<10 ms) and lasts for seconds, and could contribute to the short-term plasticity characteristics of mossy fiber synapses (Schmitz D et al, 20013 ).
I N
I L high threshold
Transients and kinetics for these channels were studied using whole-cell patch clamp recordings (Bischofberger J et al, 200213 ).
Zn2+ CA3 pyramidal neuron proximal dendrites, mossy cell proximal dendrites, and basket cell basal dendrites
Glutamate
Hippocampus CA3 pyramidal GLU cell
 -Proximal apical dendrite.Glutamate
CA3 pyramidal neuron proximal dendrites, mossy cell proximal dendrites, and basket cell basal dendrites
Dynorphin CA3 pyramidal neuron proximal dendrites, mossy cell proximal dendrites, and basket cell basal dendrites
Classical References: first publications on each compartmental property; search PubMed for complete list
1.  Liu YB, Ye GL, Liu XS, Pasternak JF and Trommer BL. (1998) GABAA currents in immature dentate gyrus granule cells. J Neurophysiol 80:2255-67 [Journal] .
2.  Isokawa M, Levesque M, Fried I and Engel J. (1997) Glutamate currents in morphologically identified human dentate granule cells in temporal lobe epilepsy. J Neurophysiol 77:3355-69 [Journal] .
3.  Schmitz D, Mellor J and Nicoll RA. (2001) Presynaptic kainate receptor mediation of frequency facilitation at hippocampal mossy fiber synapses. Science 291:1972-6 [Journal] .
4.  Valiante TA, Abdul-Ghani MA, Carlen PL and Pennefather P. (1997) Analysis of current fluctuations during after-hyperpolarization current in dentate granule neurones of the rat hippocampus. J Physiol 499 ( Pt 1):121-34.
5.  Nagerl UV and Mody I. (1998) Calcium-dependent inactivation of high-threshold calcium currents in human dentate gyrus granule cells. J Physiol 509 ( Pt 1):39-45.
6.  Beck H, Steffens R, Elger CE and Heinemann U. (1998) Voltage-dependent Ca2+ currents in epilepsy. Epilepsy Res 32:321-32.
7.  Beck H, Blümcke I, Kral T, Clusmann H, Schramm J, Wiestler OD, Heinemann U and Elger CE. (1996) Properties of a delayed rectifier potassium current in dentate granule cells isolated from the hippocampus of patients with chronic temporal lobe epilepsy. Epilepsia 37:892-901.
8.  Beck H, Ficker E and Heinemann U. (1992) Properties of two voltage-activated potassium currents in acutely isolated juvenile rat dentate gyrus granule cells. J Neurophysiol 68:2086-99 [Journal] .
9.  Lübke J, Frotscher M and Spruston N. (1998) Specialized electrophysiological properties of anatomically identified neurons in the hilar region of the rat fascia dentata. J Neurophysiol 79:1518-34 [Journal] .
10.  Jefferys JG. (1979) Initiation and spread of action potentials in granule cells maintained in vitro in slices of guinea-pig hippocampus. J Physiol 289:375-88.
11.  Reckziegel G, Beck H, Schramm J, Elger CE and Urban BW. (1998) Electrophysiological characterization of Na+ currents in acutely isolated human hippocampal dentate granule cells. J Physiol 509 ( Pt 1):139-50.
12.  Ketelaars SO, Gorter JA, van Vliet EA, Lopes da Silva FH and Wadman WJ. (2001) Sodium currents in isolated rat CA1 pyramidal and dentate granule neurones in the post-status epilepticus model of epilepsy. Neuroscience 105:109-20.
13.  Bischofberger J, Geiger JR and Jonas P. (2002) Timing and efficacy of Ca2+ channel activation in hippocampal mossy fiber boutons. J Neurosci 22:10593-602.
14.  Rockett R. (2010) Paying more than you should for outpatient procedures? Manag Care 19:29-30.