Hypothalamic Flip-Flop Circuit
●
Consolidated Wake
Orexin Tone (LH)
85 Hz
VLPO Sleep Drive
22%
Monoaminergic Output
90%
Flip-Flop Stability
0.94
85%
20%
80%
15%
Mechanistic Note: Orexin peptides (Hypocretin-1 & 2) act as an indispensable non-reciprocal stabilizer, driving monoaminergic nuclei (LC, TMN, DR) to prevent sudden, inappropriate state transitions into REM/NREM sleep.
Receptor Binding & Pharmacology Console
Endogenous Orexin-A
Select Ligand / Modulator
50 nM
1.0x (Equipotent)
OX1R (Hcrtr1)
82% Occupied
Affinity Ki:
2.4 nM
Signaling Pathway:
Gq/11 → PLCβ → IP3/Ca²⁺
Primary Phenotype:
Addiction, Stress, Panic
OX2R (Hcrtr2)
82% Occupied
Affinity Ki:
2.5 nM
Signaling Pathway:
Gq/11 + Gi/o → Depol
Primary Phenotype:
Arousal & REM Suppression
Pharmacodynamic Insight: While Dual Orexin Receptor Antagonists (DORAs) promote physiological sleep architecture without GABAergic hangover or motor ataxia, selective OX2R agonists directly replace missing hypocretinergic tone to abolish cataplexy.