Depolarizing IPSPs and depolarization by GABA of rat neostriatum cells in vitro

Misgeld, U.; Wagner, A.; Ohno, Tadao

doi:10.1007/bf00235769

Cited by 63 publications

(39 citation statements)

References 32 publications

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“…Therefore, GABAergic synapses depolarize MSNs from V rest (Misgeld et al, 1982;Koó s and Tepper, 1999) but do not trigger action potentials and hence can exert inhibitory actions (Plenz and Aertsen, 1996). The membrane potential of MSNs in vivo, under urethane or sodium pentobarbital anesthesia, oscillates between down and up states, the latter being generated by glutamatergic afferents (Wilson and Kawaguchi, 1996;Mahon et al, 2001;Tseng et al, 2001).…”

Section: Discussionmentioning

confidence: 99%

Dopamine-Deprived Striatal GABAergic Interneurons Burst and Generate Repetitive Gigantic IPSCs in Medium Spiny Neurons

Dehorter¹,

Guigoni²,

Lopez³

et al. 2009

Journal of Neuroscience

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Striatal GABAergic microcircuits modulate cortical responses and movement execution in part by controlling the activity of medium spiny neurons (MSNs). How this is altered by chronic dopamine depletion, such as in Parkinson's disease, is not presently understood. We now report that, in dopamine-depleted slices of the striatum, MSNs generate giant spontaneous postsynaptic GABAergic currents (single or in bursts at 60 Hz) interspersed with silent episodes, rather than the continuous, low-frequency GABAergic drive (5 Hz) observed in control MSNs. This shift was observed in one-half of the MSN population, including both "D 1 -negative" and "D 1 -positive" MSNs. Single GABA and NMDA channel recordings revealed that the resting membrane potential and reversal potential of GABA were similar in control and dopamine-depleted MSNs, and depolarizing, but not excitatory, actions of GABA were observed. Glutamatergic and cholinergic antagonists did not block the GABAergic oscillations, suggesting that they were generated by GABAergic neurons. In support of this, cell-attached recordings revealed that a subpopulation of intrastriatal GABAergic interneurons generated bursts of spikes in dopamine-deprived conditions. This subpopulation included low-threshold spike interneurons but not fast-spiking interneurons, cholinergic interneurons, or MSNs. Therefore, a population of local GABAergic interneurons shifts from tonic to oscillatory mode when dopamine deprived and gives rise to spontaneous repetitive giant GABAergic currents in one-half the MSNs. We suggest that this may in turn alter integration of cortical signals by MSNs.

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Section: Discussionmentioning

confidence: 99%

Dopamine-Deprived Striatal GABAergic Interneurons Burst and Generate Repetitive Gigantic IPSCs in Medium Spiny Neurons

Dehorter¹,

Guigoni²,

Lopez³

et al. 2009

Journal of Neuroscience

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“…Misgeld, Weiler, & Bak, 1980; Misgeld, Wagner & Ohno, 1982 a;Misgeld, Weiler & Cheong, 1982 b). The standard saline for pre-incubation of the slices (1 h) and perfusion of the recording chamber consisted of (mM): NaCl, 124; KCl, 5-1; 594 MgS04, 1P3; KH2PO4, 1P22; NaHCO3, 25-5; CaCl2, 2-5; glucose, 10-2; the pH was 7 4 and temperature 360C.…”

Section: Methodsmentioning

confidence: 99%

“…3B) and was still hyperpolarizing at around -60 mV even if KCl electrodes were used. Neostriatal i.p.s.p.s are blocked by bicuculline (Misgeld et al 1982 a) and their reversal potential is around -40 mV if KCl-filled electrodes are used (Misgeld,Dodt & Frotscher,597 applied to return the membrane back to the resting level. Changes in slope resistances (Fig.…”

Section: Electrical Stimulation Of Cholinergic Neurone8mentioning

confidence: 99%

Muscarinic slow excitation and muscarinic inhibition of synaptic transmission in the rat neostriatum.

Dodt¹,

Misgeld²

1986

The Journal of Physiology

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SUMMARY1. Intracellular recording from neurones in rat neostriatal slices was used to compare the muscarinic effects of endogenous acetylcholine (ACh) released from cholinergic neostriatal synapses with the action of exogenously applied muscarinic agonists.2. Repetitive electrical stimulation in the neostriatum evoked a series of fast excitatory post-synaptic potentials (e.p.s.p.s) followed by a short, variable period of input resistance decrease. In the presence of the acetylcholinesterase (AChE) inhibitor, physostigmine, these potentials were followed by a slow e

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“…A short-duration bicuculline-sensitive potential was described both in vivo (Calabresi, Mercuri, Stefani & Bernardi, 1990c) and in vitro (Misgeld, Wagner & Ohno, 1982;Calabresi, Mercuri & Bernardi, 1990 a) experiments. By contrast, although GABAB binding sites have been reported in the neostriatum (Bowery, Hudson & Price, 1987), relatively little is known concerning the localization and the electrophysiological role of GABAB receptors within this structure.…”

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confidence: 99%

Involvement of GABA systems in feedback regulation of glutamate‐and GABA‐mediated synaptic potentials in rat neostriatum.

Calabresi¹,

Mercuri²,

Murtas³

et al. 1991

The Journal of Physiology

123

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SUMMARY1. Neostriatal neurones were recorded intracellularly from a rat corticostriatal slice preparation. Depolarizing postsynaptic potentials (DPSPs) were evoked by either cortical or intrastriatal stimulation.2. Kynurenic acid (600 /tM), an antagonist of excitatory amino acids, reduced the cortically-evoked DPSPs by 88 % while the intrastriatally evoked potentials were reduced by 48 %. Bicuculline (100,tM) produced only a slight inhibition of the cortically evoked DPSPs (12 %), but clearly depressed intrastriatal potentials (52 %).3. The effects of (-)-baclofen, a y-aminobutyric acid (GABA)B receptor agonist, were studied on the cortically evoked DPSPs. In all the tested neurones (-)-baclofen, added to the superfusion medium, caused a concentration-dependent decrease of these potentials (half-maximal effect (EC50) = 800 nM). This effect was not affected by bicuculline. (-)-Baclofen did not change the membrane potential, the input resistance, current-evoked firing frequency, or postsynaptic responses to exogenously applied glutamate.4. The effects of (-)-baclofen on the DPSPs were compared to those produced by application of GABA and muscimol. GABA and muscimol decreased the DPSPs and caused a membrane depolarization coupled with a decrease of the membrane resistance. Bicuculline (100 JtM) blocked the GABA-induced changes of the membrane potential and of the resistance, but not the decrease of the synaptic potentials. All the effects produced by muscimol were blocked by bicuculline.5. Following intrastriatal stimulation a residual kynurenate-insensitive potential persisted; this potential was blocked by bicuculline (100 ,tM). (-)-Baclofen produced a dose-dependent decrease of this potential (EC50 = 800 nM). The postsynaptic responses to exogenously applied GABA were unchanged by (-)-baclofen.6. The amplitude of kynurenate and bicuculline-sensitive DPSPs were stable at a frequency of 0 1 Hz. At frequencies between 0 3 and 3 Hz both these potentials were attenuated with the second stimulus and after about five stimuli a steady state was reached. Membrane potential and input resistance were not affected by these frequencies of stimulation.* To whom correspondence should be addressed. MS 8751P. CALABRESI AND OTHERS 7. Application of the GABA uptake inhibitor nipecotic acid (100-300 1uM) clearly reduced the amplitude of both kynurenate-and bicuculline-sensitive DPSPs evoked at low frequencies of stimulation (0-01-0{3 Hz), but had lower effects at higher stimulation rates (1-3 Hz). Application of nipecotic acid increased the duration of membrane responses to exogenously applied GABA.8. Applications of either 2-hydroxy-saclofen (100 JM) or phaclofen (0-7-1 mm), antagonists of the GABAB receptors, produced a parallel shift to the right of the dose-response curve of the effect of (-)-baclofen on the bicuculline-sensitive DPSPs, but did not significantly antagonize the effect of this agonist on the kynurenatesensitive DPSPs. 2-Hydroxy-saclofen produced an increase in the amplitude of bicuculline-sensitive DPSPs, while i...

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Depolarizing IPSPs and depolarization by GABA of rat neostriatum cells in vitro

Cited by 63 publications

References 32 publications

Dopamine-Deprived Striatal GABAergic Interneurons Burst and Generate Repetitive Gigantic IPSCs in Medium Spiny Neurons

Dopamine-Deprived Striatal GABAergic Interneurons Burst and Generate Repetitive Gigantic IPSCs in Medium Spiny Neurons

Muscarinic slow excitation and muscarinic inhibition of synaptic transmission in the rat neostriatum.

Involvement of GABA systems in feedback regulation of glutamate‐and GABA‐mediated synaptic potentials in rat neostriatum.

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