Vassalli et al.'s study does not involve or provide additional data regarding influenza virus, influenza vaccines, human samples, animal models of narcolepsy, or experiments related to mimicry and cross-reactivity. They present data on the distribution of hypocretin (HCRT) (also known as orexin) receptors in the brain of an engineered mouse developed by them.

Orexins (also called hypocretins) are peptide neurotransmitters expressed in neurons of the lateral hypothalamic area (LHA). Mice lacking the orexin peptides develop narcolepsy-like symptoms, whereas mice with a selective loss of the orexin neurons develop hypophagia and severe obesity in addition to the narcolepsy phenotype. These different phenotypes suggest that orexin neurons may contain ne...

Sleep is important and required for the survival and normal homeostasis of vertebrates. Disturbances in the sleep-wake cycle can lead to many sleep disorders, one of which is narcolepsy. Narcolepsy is a disabling sleep disorder characterized by excessive daytime sleep, cataplexy (sudden loss of muscle tone in response to strong emotion or laughter), hallucinations, and sleep paralysis. To date,...

Orexin-A (OX-A) and orexin-B (OX-B) (hypocretin 1 and hypocretin 2) are synthesized in neurons of the perifornical, dorsomedial, lateral, and posterior hypothalamus. The locus coeruleus (LC) receives the densest extrahypothalamic projections of the orexin (OX) system. Recent evidence suggests that descending projections of the LC have a facilitatory role in the regulation of muscle tone. The po...

The hypocretin (Hcrt), also known as orexin, peptides are essential for arousal stability. Here we discuss background information about the interaction of Hcrt with other neuromodulators, including norepinephrine and acetylcholine probed with optogenetics. We conclude that Hcrt neurons integrate metabolic, circadian and limbic inputs and convey this information to a network of neuromodulators, ...

Orexin, also called hypocretin, is a neuropeptide that acts on central nervous system receptors to promote arousal. Suvorexant, its receptor antagonist, generates interest as a medication to treat insomnia. Suvorexant helps in decreasing wakefulness by counteracting orexin activity. Its low side effect potential may offer considerable benefit. Compared with other sleep aids, diminished drowsine...

Drug addiction is a chronic illness characterized by high rates of relapse. Relapse to drug use can be triggered by re-exposure to drug-associated cues, stressful events, or the drug itself after a period of abstinence. Pharmacological intervention to reduce the impact of relapse-instigating factors offers a promising target for addiction treatment. Growing evidence has implicated an important ...

Hypocretin (orexin), a neuropeptide synthesized exclusively in the perifornical/lateral hypothalamus, is critical for drug seeking and relapse, but it is not clear how the circuitry centred on hypocretin-producing neurons (hypocretin neurons) is modified by drugs of abuse and how changes in this circuit might alter behaviours related to drug addiction. In this study, we show that repeated, but ...

Hypocretin/orexin neurons regulate many behavioral functions, including addiction. Nicotine acts through nicotinic acetylcholine receptors (nAChRs) to alter firing rate of neurons throughout the brain, leading to addictionrelated behaviors. While nAChRs are expressed in the hypothalamus and cholinergic fibers project to this structure, it is unclear how acetylcholine modulates the activity of h...

Neurons containing the peptide hypocretin, also known as orexin, were recently implicated in the human sleep disorder narcolepsy. Hypocretin neurons are located only in the lateral hypothalamus from where they innervate virtually the entire brain and spinal cord. This peptide is believed to be involved in regulating feeding and wakefulness. However, to fully understand what other behaviors are ...