Narcolepsy-cataplexy sleep

Broughton, R., Krupa, S., Boucher, B., Rivers, M. 8r Mullington, J. (1998). Impaired circadian waking arousal in narcolepsy-cataplexy. Sleep Res. Online 1, 159-65. 

Newman, J. and Bough ton, R., Pupillometric assessment of excessive daytime sleepiness in narcolepsy-cataplexy, Sleep, 14, 121, 1991. 

Narcolepsy, a sleep disorder characterized by excessive daytime sleepiness and cataplexy, may be caused by the lack of hypocretin mRNA and peptides in humans (Peyron et al., 2000) or a disruption of the hypocretin receptor 2 or its ligand in dogs and mice (Lin et al., 1999 Chemelli et al., 1999). Hypocretin-containing neurons are located exclusively in the dorsomedial, lateral, and perifornical hypothalamic areas (Peyron et al., 1998). Two hypocretin sequences, Hcrt-1 (orexin-A) and Hcrt-2 (orexin-B), are generated from a single preprohypocretin (De Lecea et al., 1998 Peyron et al, 1998 Sakurai et al, 1998). Axons from these neurons are found in the hypothalamus, locus coeruleus (LC), raphe nuclei, tuberomamillary nucleus, midline thalamus, all levels of spinal cord, sympathetic and parasympathetic centers, and many other brain regions... 

Orexins in sleep and wakefulness rodent models of narcolepsy-cataplexy... 

Milder narcolepsy-cataplexy comparable to canine narcolepsy. OX2R signahng stabilizes wakefulness and also contributes to REM sleep gating Severe narcolepsy-cataplexy... 

Severe narcolepsy-cataplexy comparable to the human disorder. Cataplectic episodes can be separated from wakefulness-REM sleep transitions... 

Broughton, R Dunham, W., Newman, J. et al. (1988). Ambulatory 24 hour sleep-wake monitoring in narcolepsy-cataplexy compared to matched controls. Electroencephalogr. Clin. Neurophysiol. 70, 473-81. 

Narcolepsy can usually be distinguished from insomnia by the presence of one of the auxiliary symptoms (cataplexy, sleep paralysis, hypnagogic hallucinations). When the diagnosis remains unclear, then a sleep study is necessary. 

Antidepressants. In addition to increasing alertness, the psychostimulants also mildly suppress the REM phase of sleep. Because the auxiliary symptoms of narcolepsy (cataplexy, hypnagogic hallucinations, and sleep paralysis) are basically... 

Narcolepsy is another medically recognized indication for the use of the psychomotor stimulants. This disorder is characterized by sleep attacks, particularly during the day, sudden loss of muscle tone cataplexy), sleep paralysis, and vivid visual and auditory nightmares that may persist into the waking state. Drugs that influence the central action of adrenomimetic amines re-... 

One of the oldest uses for dextroamphetamines is in the treatment of narcolepsy, a sleep disorder characterized by constant daytime fatigue and sleepiness, with a disturbance in nighttime REM sleep (the period of sleep when dreams occur). During the day or other periods of time when they would normaly be awake, people with narcolepsy often experience sudden episodes of REM sleep. They may also suffer from sleep paralysis and/or cataplexy, an abmpt, total loss of muscle control. Central nervous system stimulants like dextroamphetamine help to relieve these symptoms. 

Sleepiness is a primary symptom of narcolepsy, often preceding the onset of the other well-known symptoms of the disease, namely cataplexy, sleep paralysis, and hypnagogic hallucinations (44). Evaluation of the MSLT of narcoleptic patients has demonstrated a short sleep latency (<5 min) and multiple sleep-onset REM periods (SOREMPs). The more specific finding in the MSLT of narcoleptic patients is more than 2 SOREMPs, shown to reach a specificity of 99% by Amira et al. (45), which further increased to 99.2% if 3 SOREMPs were recorded (46). On the other hand, more than one SOREMP can occur in nonnarcoleptic patients, such as those with sleep apnea, sleep deprivation, depression, periodic limb movements, circadian rhythm disruption, or withdrawal from REM-suppressing medications (5,47). Thus, the findings of the MSLT, which is always performed for suspected narcoleptic patients, must be interpreted in view of the clinical history and nocturnal PSG. 

Broughton R, Valley V, Aguirre M, Roberts J, Suwalski W, Dunham W (1986) Excessive daytime sleepiness and the pathophysiology of narcolepsy-cataplexy a laboratory perspective. Sleep 9 205-215... 

Mignot E, Guilleminault C, Bowersox S, Fruhstorfer B, Nishino S, Maddaluno J, Cia-raneho R, Dement WC (1989) Central alpha-1 adrenoceptor subtypes in narcolepsy-cataplexy a disorder of REM sleep. Brain Res 490 186-191... 

Four characteristic symptoms differentiate narcolepsy from other sleep disorders, and are known as the narcolepsy tetrad sleep attacks, cataplexy, hypnagogic hallucinations, and sleep paralysis. Individuals with narcolepsy complain of excessive daytime sleepiness, with sleep attacks that last up to 30 minutes. Individuals complain of hypersomnia, fatigue, impaired performance, and disturbed nighttime sleep. 

In the sleep laboratory, individuals with narcolepsy have impairment of both the onset and offset of REM and NREM sleep. Narcoleptics are unable to maintain either REM or NREM sleep, which results in multiple arousals duriug the uight. It is thought that the REM sleep disturbauce duriug the uight causes the symptoms of cataplexy, sleep paralysis, aud hypuagogic halluciuatious. ... 

The sleep disorder narcolepsy, which affects around 1 in every 2000 people, is characterized by a tetrad of symptoms excessive daytime sleepiness, cataplexy (loss of muscle tone triggered by emotional arousal), hypnagogic hallucinations,... 

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