OBJECTIVES This study has been carried out to test the clinical hypothesis of personal smell as a hint to the diagnosis of narcoleptic patients. METHODS Sweat samples from narcoleptic and healthy controls were tested independently by two trained dogs and their positive or negative detection compared to the gold standard diagnosis for narcolepsy. Neither trainer nor dog knew the source of the ...

Despite strong circumstantial evidence for the autoimmune hypothesis of narcolepsy, conventional immunological methods have failed to detect an autoantibody. This study investigated the real-time effects of narcoleptic immunoglobulins on a spontaneous colonic migrating motor complex (CMMC) preparation. IgG from patients with narcolepsy with cataplexy or healthy controls was added directly to is...

OBJECTIVES The aim of this study was to investigate the influence of age on the manifestation of narcolepsy symptoms and cognitive difficulties in patients with narcolepsy. METHODS A total of 321 participants were included in the study: 157 were patients with narcolepsy from two Sleep Disorders Clinics and 164 were control participants. Narcoleptic patients were evaluated and diagnosed at the...

A dysfunction of the orexin (hypocretin) system in the hypothalamus has recently been linked to the pathogenesis of narcolepsy. The authors used in vivo proton MR spectroscopy to assess the N-acetylaspartate (NAA) content in the hypothalamus of narcoleptic patients. Hypothalamic NAA/creatine-phosphocreatine was reduced in narcoleptic patients compared with control subjects (p < 0.01). Hypothala...

The narcoleptic syndrome is a life-long and sometimes familial disorder in which there is a disturbance of the rapid eye movement phase of sleep. Patients with periodic sleep in the daytime but no other symptoms seldom develop the narcoleptic syndrome and have a separate unrelated disorder. Twelve patients with the narcoleptic syndrome were treated separately with l(-) amphetamine and d(+) amph...

BACKGROUND Narcolepsy is a severe sleep-wake cycle disorder resulting in most cases from a lack of orexin, the energy balance-regulating hormone. Narcoleptic patients have been reported to suffer from an excess morbidity of Type 2 diabetes, even after correction for their often elevated body mass index. METHODS To explore whether narcolepsy is specifically associated with a propensity to deve...

All Doberman pinschers and Labrador retrievers homozygous for a mutation of the hypocretin (orexin) receptor-2 (hcrtr2) gene develop narcolepsy under normal conditions. Degenerative changes and increased display of major histocompatibility complex class II antigens have been linked to symptom onset in genetically narcoleptic Doberman pinschers. This suggests that the immune system may contribut...

Narcolepsy patients often suffer from insomnia in addition to excessive daytime sleepiness. Narcoleptic animals also show behavioral instability characterized by frequent transitions between all vigilance states, exhibiting very short bouts of NREM sleep as well as wakefulness. The instability of wakefulness states in narcolepsy is thought to be due to deficiency of orexins, neuropeptides produ...

Neuroimaging techniques have refined the characterization of neural structures involved in the regulation of normal sleep-wake cycle in healthy humans. Yet brain imaging studies in patients with sleep disorders still remain scarce. In narcoleptic patients, structural and functional brain imaging studies have suggested the involvement of the hypothalamus in the pathophysiology of narcolepsy, pla...

Neurons containing the neuropeptide orexin (hypocretin) are located exclusively in the lateral hypothalamus and send axons to numerous regions throughout the central nervous system, including the major nuclei implicated in sleep regulation. Here, we report that, by behavioral and electroencephalographic criteria, orexin knockout mice exhibit a phenotype strikingly similar to human narcolepsy pa...