STUDY OBJECTIVES: GABAergic transmission in the oral part of the pontine reticular formation (PnO) increases wakefulness. The hypothalamic peptide hypocretin-1 (orexin A) promotes wakefulness, and the PnO receives hypocretinergic input. The present study tested the hypothesis that PnO administration of hypocretin-1 increases PnO GABA levels and increases wakefulness. This study also tested the hypothesis that wakefulness is either increased or decreased, respectively, by PnO administration of drugs known to selectively increase or decrease GABA levels. DESIGN: Awithin-subjects design was used for microdialysis and microinjection experiments. SETTING: University of Michigan. PATIENTS OR PARTICIPANTS: Experiments were performed using adult male Crl:CD (SD)IGS BR (Sprague-Dawley) rats (n=46). INTERVENTIONS: PnO administration of hypocretin-1, nipecotic acid (a GABA uptake inhibitor that increases extracellular GABA levels), 3-mercaptopropionic acid (a GABA synthesis inhibitor that decreases extracellular GABA levels; 3-MPA), and Ringer solution (vehicle control). MEASUREMENTS AND RESULTS: Dialysis administration of hypocretin-1 to the PnO caused a statistically significant, concentration-dependent increase in PnO GABA levels. PnO microinjection of hypocretin-1 or nipecotic acid caused a significant increase in wakefulness and a significant decrease in non-rapid eye movement (NREM) sleep and REM sleep. Microinjecting 3-MPA into the PnO caused a significant increase in NREM sleep and REM sleep and a significant decrease in wakefulness. CONCLUSIONS: An increase or a decrease in PnO GABA levels causes an increase or decrease, respectively, in wakefulness. Hypocretin-1 may promote wakefulness, at least in part, by increasing GABAergic transmission in the PnO.
STUDY OBJECTIVES: GABAergic transmission in the oral part of the pontine reticular formation (PnO) increases wakefulness. The hypothalamic peptide hypocretin-1 (orexin A) promotes wakefulness, and the PnO receives hypocretinergic input. The present study tested the hypothesis that PnO administration of hypocretin-1 increases PnO GABA levels and increases wakefulness. This study also tested the hypothesis that wakefulness is either increased or decreased, respectively, by PnO administration of drugs known to selectively increase or decrease GABA levels. DESIGN: Awithin-subjects design was used for microdialysis and microinjection experiments. SETTING: University of Michigan. PATIENTS OR PARTICIPANTS: Experiments were performed using adult male Crl:CD (SD)IGS BR (Sprague-Dawley) rats (n=46). INTERVENTIONS: PnO administration of hypocretin-1, nipecotic acid (a GABA uptake inhibitor that increases extracellular GABA levels), 3-mercaptopropionic acid (a GABA synthesis inhibitor that decreases extracellular GABA levels; 3-MPA), and Ringer solution (vehicle control). MEASUREMENTS AND RESULTS: Dialysis administration of hypocretin-1 to the PnO caused a statistically significant, concentration-dependent increase in PnO GABA levels. PnO microinjection of hypocretin-1 or nipecotic acid caused a significant increase in wakefulness and a significant decrease in non-rapid eye movement (NREM) sleep and REM sleep. Microinjecting 3-MPA into the PnO caused a significant increase in NREM sleep and REM sleep and a significant decrease in wakefulness. CONCLUSIONS: An increase or a decrease in PnO GABA levels causes an increase or decrease, respectively, in wakefulness. Hypocretin-1 may promote wakefulness, at least in part, by increasing GABAergic transmission in the PnO.
Authors: L Lin; J Faraco; R Li; H Kadotani; W Rogers; X Lin; X Qiu; P J de Jong; S Nishino; E Mignot Journal: Cell Date: 1999-08-06 Impact factor: 41.582
Authors: C Peyron; D K Tighe; A N van den Pol; L de Lecea; H C Heller; J G Sutcliffe; T S Kilduff Journal: J Neurosci Date: 1998-12-01 Impact factor: 6.167
Authors: R M Chemelli; J T Willie; C M Sinton; J K Elmquist; T Scammell; C Lee; J A Richardson; S C Williams; Y Xiong; Y Kisanuki; T E Fitch; M Nakazato; R E Hammer; C B Saper; M Yanagisawa Journal: Cell Date: 1999-08-20 Impact factor: 41.582
Authors: Ritchie E Brown; Radhika Basheer; James T McKenna; Robert E Strecker; Robert W McCarley Journal: Physiol Rev Date: 2012-07 Impact factor: 37.312