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Ionotropic GABA and glycine receptor subunit composition in human pluripotent stem cell-derived excitatory cortical neurones.

James OT, Livesey MR, Qiu J, Dando O, Bilican B, Haghi G, Rajan R, Burr K, Hardingham GE, Chandran S, Kind PC, Wyllie DJ - J. Physiol. (Lond.) (2014)

Bottom Line: Taken together our data support the notion that hECN GABAARs have an α2/3β3γ2 subunit composition - a composition that also predominates in immature rodent cortex.GlyRs expressed by hECNs were activated by glycine with an EC50 of 167 μm.RNA-seq indicates GlyRs are likely to be composed of α2 and β subunits.

View Article: PubMed Central - PubMed

Affiliation: Centre for Integrative Physiology, University of Edinburgh, Edinburgh, EH8 9XD, UK Centre for Brain Development and Repair, Institute for Stem Cell Biology and Regenerative Medicine, National Centre for Biological Sciences, Bangalore, 560065, India Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.

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Modulation of hECN GABAARs by intravenous anesthetics, SCS, furosemide and zolipidemA, upper panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by propofol. A, middle panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by etomidate. A, lower panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by SCS. Calibration bars: 100 pA, 50 s (upper); 100 pA, 50 s (middle); 250 pA, 50 s (lower). B, mean percentage modulation GABA-induced currents by the allosteric modulators propofol (10 μm; n = 8, N = 2), etomidate (3 μm; n = 6, N = 1) and SCS (1 μm; n = 8, N = 2). C, mean percentage direct activation propofol and etomidate expressed with respect to control responses to GABA. D, upper panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by furosemide. D, lower panel: example trace showing potentiation of GABA-mediated whole-cell currents by zolpidem (n = 6–8, N = 2 for each condition). Calibration bars: 150 pA, 50 s (upper); 100 pA, 50 s (lower). E, mean percentage modulation GABA-induced currents by the allosteric modulators furosemide (100 μm) and zolpidem (50 nm and 500 nm).
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fig03: Modulation of hECN GABAARs by intravenous anesthetics, SCS, furosemide and zolipidemA, upper panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by propofol. A, middle panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by etomidate. A, lower panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by SCS. Calibration bars: 100 pA, 50 s (upper); 100 pA, 50 s (middle); 250 pA, 50 s (lower). B, mean percentage modulation GABA-induced currents by the allosteric modulators propofol (10 μm; n = 8, N = 2), etomidate (3 μm; n = 6, N = 1) and SCS (1 μm; n = 8, N = 2). C, mean percentage direct activation propofol and etomidate expressed with respect to control responses to GABA. D, upper panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by furosemide. D, lower panel: example trace showing potentiation of GABA-mediated whole-cell currents by zolpidem (n = 6–8, N = 2 for each condition). Calibration bars: 150 pA, 50 s (upper); 100 pA, 50 s (lower). E, mean percentage modulation GABA-induced currents by the allosteric modulators furosemide (100 μm) and zolpidem (50 nm and 500 nm).

Mentions: The presence of β subunits in hECN GABAARs was confirmed by the potentiation by the intravenous anaesthetic propofol (10 μm) of GABA (EC30; 120 μm)-evoked currents which resulted in robust potentiation of the control current responses by 144 % ± 29 % (Fig. 3A and B; P = 0.002 vs. control, unpaired t test, n = 8, N = 2; Sanna et al. 1995; Hill-Venning et al. 1997). Furthermore, direct activation of GABAARs was observed when propofol (100 μm) was applied on its own (98 ± 21 % relative to GABA (EC30; 120 μm)-evoked control; n = 7, N = 2; Fig. 3A and C). The intravenous anaesthetic etomidate (3 μm), which is selective for β2/3 subunit-containing GABAARs (Hill-Venning et al. 1997), also potentiated GABA (EC30; 120 μm)-evoked currents by 75 ± 20 % (Fig. 3A and B; P = 0.01 vs. control, unpaired t test, n = 6, N = 1) while application on its own and at a higher concentration (300 μm) directly activated GABAARs (116 ± 23 % relative to GABA (EC30; 120 μm)-evoked control; n = 6, N = 1). Taken together, these data suggest the presence of a large complement of β2/3-containing GABAARs. The absence of β1-containing GABAARs was indicated by the fact that the selective inhibitor of β1-containing GABAARs, SCS (Thompson et al. 2004), failed to antagonise GABA (EC30; 120 μm)-evoked currents (Fig. 3A and B; SCS vs. control, P = 0.27 vs. control, unpaired t test, n = 8, N = 2).


Ionotropic GABA and glycine receptor subunit composition in human pluripotent stem cell-derived excitatory cortical neurones.

James OT, Livesey MR, Qiu J, Dando O, Bilican B, Haghi G, Rajan R, Burr K, Hardingham GE, Chandran S, Kind PC, Wyllie DJ - J. Physiol. (Lond.) (2014)

Modulation of hECN GABAARs by intravenous anesthetics, SCS, furosemide and zolipidemA, upper panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by propofol. A, middle panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by etomidate. A, lower panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by SCS. Calibration bars: 100 pA, 50 s (upper); 100 pA, 50 s (middle); 250 pA, 50 s (lower). B, mean percentage modulation GABA-induced currents by the allosteric modulators propofol (10 μm; n = 8, N = 2), etomidate (3 μm; n = 6, N = 1) and SCS (1 μm; n = 8, N = 2). C, mean percentage direct activation propofol and etomidate expressed with respect to control responses to GABA. D, upper panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by furosemide. D, lower panel: example trace showing potentiation of GABA-mediated whole-cell currents by zolpidem (n = 6–8, N = 2 for each condition). Calibration bars: 150 pA, 50 s (upper); 100 pA, 50 s (lower). E, mean percentage modulation GABA-induced currents by the allosteric modulators furosemide (100 μm) and zolpidem (50 nm and 500 nm).
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
getmorefigures.php?uid=PMC4215781&req=5

fig03: Modulation of hECN GABAARs by intravenous anesthetics, SCS, furosemide and zolipidemA, upper panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by propofol. A, middle panel: example trace showing potentiation of GABA-mediated whole-cell currents and direct activation of GABAARs by etomidate. A, lower panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by SCS. Calibration bars: 100 pA, 50 s (upper); 100 pA, 50 s (middle); 250 pA, 50 s (lower). B, mean percentage modulation GABA-induced currents by the allosteric modulators propofol (10 μm; n = 8, N = 2), etomidate (3 μm; n = 6, N = 1) and SCS (1 μm; n = 8, N = 2). C, mean percentage direct activation propofol and etomidate expressed with respect to control responses to GABA. D, upper panel: example trace showing lack of inhibition of GABA-mediated whole-cell currents by furosemide. D, lower panel: example trace showing potentiation of GABA-mediated whole-cell currents by zolpidem (n = 6–8, N = 2 for each condition). Calibration bars: 150 pA, 50 s (upper); 100 pA, 50 s (lower). E, mean percentage modulation GABA-induced currents by the allosteric modulators furosemide (100 μm) and zolpidem (50 nm and 500 nm).
Mentions: The presence of β subunits in hECN GABAARs was confirmed by the potentiation by the intravenous anaesthetic propofol (10 μm) of GABA (EC30; 120 μm)-evoked currents which resulted in robust potentiation of the control current responses by 144 % ± 29 % (Fig. 3A and B; P = 0.002 vs. control, unpaired t test, n = 8, N = 2; Sanna et al. 1995; Hill-Venning et al. 1997). Furthermore, direct activation of GABAARs was observed when propofol (100 μm) was applied on its own (98 ± 21 % relative to GABA (EC30; 120 μm)-evoked control; n = 7, N = 2; Fig. 3A and C). The intravenous anaesthetic etomidate (3 μm), which is selective for β2/3 subunit-containing GABAARs (Hill-Venning et al. 1997), also potentiated GABA (EC30; 120 μm)-evoked currents by 75 ± 20 % (Fig. 3A and B; P = 0.01 vs. control, unpaired t test, n = 6, N = 1) while application on its own and at a higher concentration (300 μm) directly activated GABAARs (116 ± 23 % relative to GABA (EC30; 120 μm)-evoked control; n = 6, N = 1). Taken together, these data suggest the presence of a large complement of β2/3-containing GABAARs. The absence of β1-containing GABAARs was indicated by the fact that the selective inhibitor of β1-containing GABAARs, SCS (Thompson et al. 2004), failed to antagonise GABA (EC30; 120 μm)-evoked currents (Fig. 3A and B; SCS vs. control, P = 0.27 vs. control, unpaired t test, n = 8, N = 2).

Bottom Line: Taken together our data support the notion that hECN GABAARs have an α2/3β3γ2 subunit composition - a composition that also predominates in immature rodent cortex.GlyRs expressed by hECNs were activated by glycine with an EC50 of 167 μm.RNA-seq indicates GlyRs are likely to be composed of α2 and β subunits.

View Article: PubMed Central - PubMed

Affiliation: Centre for Integrative Physiology, University of Edinburgh, Edinburgh, EH8 9XD, UK Centre for Brain Development and Repair, Institute for Stem Cell Biology and Regenerative Medicine, National Centre for Biological Sciences, Bangalore, 560065, India Euan MacDonald Centre for MND Research, University of Edinburgh, Edinburgh, EH16 4SB, UK.

Show MeSH
Related in: MedlinePlus