Substantia nigra pars compacta DA cell

- - BG - SubNigra - PRINC - pars compacta - - da
Properties are:  Present   Absent 
Input Receptors
Intrinsic Currents
Output Transmitters
Distal apical dendrite
D2
I p,q
The action potential has a pronounced Ca component on its falling phase (Yung WH et al, 1991 [guinea pig]4 ). reviewed in (Häusser M et al, 1995 [rat]5 ).
I Na,t
the back-propagating action potential may be important for the dendritic release of dopamine" (Häusser M et al, 1995 [rat]5 ).
I Calcium
Using differential polarization through applied electric fields, cell bodies and dendrites have been activated in effective isolation during intracellular recordings in vitro. In neurons located in the rostral substantia nigra, the dendrites are shown to have both HVA and LVA channels. HVA conductance appears to be exclusively dendritic. By contrast, in more caudally located cells HVA calcium spikes were located principally in the cell body (Hounsgaard J et al, 19929 ).
Dopamine -----
DA is released from dendrites (Geffen LB et al, 1976 [rat]6 ). Korf et al, 1976; Cheramy et al 1981) by backpropagating impulse (Häusser M et al, 1995 [rat]5 ). acts on D2 autoreceptors (Lacey MG et al, 1987 [rat]10 ). 1990) causing hyperpolarization, and presynaptic GABAb receptors causing enhancement of synaptic inhibition (Cameron and Williams, 1993). (Reviewed in (Häusser M et al, 1995 [rat]5 ).
Middle apical dendrite
I Na,t
the back-propagating action potential may be important for the dendritic release of dopamine" (Häusser M et al, 1995 [rat]5 ).
I p,q
The action potential has a pronounced Ca component on its falling phase (Yung WH et al, 1991 [guinea pig]4 ). reviewed in (Häusser M et al, 1995 [rat]5 ). (Yung WH et al, 1991 [guinea pig]4 ). (Geffen LB et al, 1976 [rat]6 ). (Stuart GJ and Sakmann B, 1994 [rat]7 ).
I Calcium
Using differential polarization through applied electric fields, cell bodies and dendrites have been activated in effective isolation during intracellular recordings in vitro. In neurons located in the rostral substantia nigra, the dendrites are shown to have both HVA and LVA channels. HVA conductance appears to be exclusively dendritic. By contrast, in more caudally located cells HVA calcium spikes were located principally in the cell body (Hounsgaard J et al, 19929 ).
Dopamine -----
DA is released from dendrites (Geffen LB et al, 1976 [rat]6 ). Korf et al, 1976; Cheramy et al 1981) by backpropagating impulse (Häusser M et al, 1995 [rat]5 ). acts on D2 autoreceptors (Lacey MG et al, 1987 [rat]10 ). 1990) causing hyperpolarization, and presynaptic GABAb receptors causing enhancement of synaptic inhibition (Cameron and Williams, 1993). (Reviewed in (Häusser M et al, 1995 [rat]5 ).
Proximal apical dendrite
I Na,t
the back-propagating action potential may be important for the dendritic release of dopamine" (Häusser M et al, 1995 [rat]5 ).
I p,q
The action potential has a pronounced Ca component on its falling phase (Yung WH et al, 1991 [guinea pig]4 ). reviewed in (Häusser M et al, 1995 [rat]5 ).
I Calcium
Using differential polarization through applied electric fields, cell bodies and dendrites have been activated in effective isolation during intracellular recordings in vitro. In neurons located in the rostral substantia nigra, the dendrites are shown to have both HVA and LVA channels. HVA conductance appears to be exclusively dendritic. By contrast, in more caudally located cells HVA calcium spikes were located principally in the cell body (Hounsgaard J et al, 19929 ).
Dopamine -----
DA is released from dendrites (Geffen LB et al, 1976 [rat]6 ). Korf et al, 1976; Cheramy et al 1981) by backpropagating impulse (Häusser M et al, 1995 [rat]5 ). acts on D2 autoreceptors (Lacey MG et al, 1987 [rat]10 ). 1990) causing hyperpolarization, and presynaptic GABAb receptors causing enhancement of synaptic inhibition (Cameron and Williams, 1993). (Reviewed in (Häusser M et al, 1995 [rat]5 ).
Distal basal dendrite
Middle basal dendrite
Proximal basal dendrite
Soma
NMDA
Using conventional or perforated-patch whole cell recordings, SNc neurons acutely dissociated from P4 to P16 rats NMDA (100 nM, V(hold) = -60 mV) evoked inward, APV-sensitive currents (56.4 +/- 8.6 pA) in all tested neurons (n = 29). Strong depolarizing responses were observed under current-clamp (Lin JY and Lipski J, 20011 ). The functional properties of NMDA receptors were studied in acute slices. Little variability in functional properties was found in different types of basal ganglia neurons (Götz T et al, 1997 [rat]2 ).
AMPA
The functional properties of AMPA receptors were studied in acute slices. It was found that AMPARs expressed in different types of basal ganglia neurons were markedly diverse (Götz T et al, 1997 [rat]2 ).
GabaA
Single unit extracellular recordings showed a short latency GABAA inhibition that arises from the axon collaterals of pars reticulata projection neurons (Tepper JM et al, 1995 [rat]3 ).
I p,q
The action potential has a pronounced Ca component on its falling phase (Yung WH et al, 1991 [guinea pig]4 ). reviewed in (Häusser M et al, 1995 [rat]5 ).
I Na,t
I K,Ca
Intracellular recordings showed that Apamin-sensitive IKCa regulate pacemaker activity in these neurons (Ping HX and Shepard PD, 1996 [rat]8 ).
I Calcium
Using differential polarization through applied electric fields, cell bodies and dendrites have been activated in effective isolation during intracellular recordings in vitro. In neurons located in the rostral substantia nigra, the dendrites are shown to have both HVA and LVA channels. HVA conductance appears to be exclusively dendritic. By contrast, in more caudally located cells HVA calcium spikes were located principally in the cell body (Hounsgaard J et al, 19929 ).
Axon hillock
I K
I Na,t
Axon fiber
I Na,t
Axon terminal
I N
Dopamine
Neostriatum medium spiny direct pathway GABA cell
 -Distal equivalent dendrite.D1
 -Middle equivalent dendrite.D1
 -Proximal equivalent dendrite.D1
Medium Spiny Neuron: Ded, Dem, Dep
Input from dopaminergic neurons in the substantia nigra; causes small depolarization? sometimes a decrease in firing rate; modulates anomalous rectification of dendritic membrane (I IR)?
Classical References: first publications on each compartmental property; search PubMed for complete list
1.  Lin JY and Lipski J. (2001) Dopaminergic substantia nigra neurons express functional nmda receptors in postnatal rats. J Neurophysiol 85:1336-9 [Journal] .
2.  Götz T, Kraushaar U, Geiger J, Lübke J, Berger T and Jonas P. (1997) Functional properties of AMPA and NMDA receptors expressed in identified types of basal ganglia neurons. J Neurosci 17:204-15.
3.  Tepper JM, Martin LP and Anderson DR. (1995) GABAA receptor-mediated inhibition of rat substantia nigra dopaminergic neurons by pars reticulata projection neurons. J Neurosci 15:3092-103.
4.  Yung WH, Häusser MA and Jack JJ. (1991) Electrophysiology of dopaminergic and non-dopaminergic neurones of the guinea-pig substantia nigra pars compacta in vitro. J Physiol 436:643-67.
5.  Häusser M, Stuart G, Racca C and Sakmann B. (1995) Axonal initiation and active dendritic propagation of action potentials in substantia nigra neurons. Neuron 15:637-47.
6.  Geffen LB, Jessell TM, Cuello AC and Iversen LL. (1976) Release of dopamine from dendrites in rat substantia nigra. Nature 260:258-60.
7.  Stuart GJ and Sakmann B. (1994) Active propagation of somatic action potentials into neocortical pyramidal cell dendrites. Nature 367:69-72 [Journal] .
8.  Ping HX and Shepard PD. (1996) Apamin-sensitive Ca(2+)-activated K+ channels regulate pacemaker activity in nigral dopamine neurons. Neuroreport 7:809-14.
9.  Hounsgaard J, Nedergaard S and Greenfield SA. (1992) Electrophysiological localization of distinct calcium potentials at selective somatodendritic sites in the substantia nigra. Neuroscience 50:513-8.
10.  Lacey MG, Mercuri NB and North RA. (1987) Dopamine acts on D2 receptors to increase potassium conductance in neurones of the rat substantia nigra zona compacta. J Physiol 392:397-416.