Intracellular energy status regulates activity in hypocretin/orexin neurones: a link between energy and behavioural states - PubMed (original) (raw)

A, ‘run down’ of _V_m in Hcrt neurones after the dialysis of pipette solution containing 2 m

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ATP into Hcrt neurones. Top and middle panels, raw traces of _V_m and APs recorded in Hcrt neurones under current clamp in perforated (grey) and conventional (with 2 m

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ATP in pipette solution, black) whole-cell modes. Bottom, time courses of _V_m in Hcrt neurones examined under current clamp in perforated (grey, n = 6) and conventional (black, n = 29) whole-cell modes. Scale bar for the inset: 20 mV, 100 ms. B, the effects of [ATP]i on _V_m in Hcrt neurones. Top, sample traces of _V_m recorded with ATP levels at 1, 3 and 5 m

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in the pipette solution. Bottom, pooled results from all cells tested at various ATP levels (1–6 m

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) and undisturbed ATP levels (P, perforated recording). C and D, the time courses and pooled results show effects of the KATP channel blocker tolbutamide on _V_m in Hcrt neurones at a low (2 m

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, filled circles/bars) and an intact (open circles/bars) [ATP]i. E and F, time course and pooled results show that diazoxide significantly induces a hyperpolarization of _V_m in Hcrt neurones with undisturbed [ATP]i. G, pooled results show that changes in intracellular ADP levels at the ATP/ADP ratios within the physiological range do not significantly alter _V_m in Hcrt neurones. ATP (concentration was fixed at 2 m

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) and ADP (at different concentrations according to the ATP/ADP ratios) were included in the pipette solution when conventional whole-cell recording was performed in Hcrt neurones. H, time courses of _V_m in ARC neurones examined under current clamp in perforated (circles) and conventional whole-cell modes with 0 (diamonds), 0.5 (triangles) and 2 m

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ATP (squares) in the pipette solution. *P < 0.05, t test.