Which neurotransmitter is associated with narcolepsy?

Orexin, also known as hypocretin, is the neurotransmitter that plays a crucial role in regulating arousal, wakefulness, and appetite. In the context of narcolepsy, particularly type 1 narcolepsy, there is a significant deficiency of orexin in the brain, which leads to excessive daytime sleepiness and sudden episodes of REM sleep. This deficiency disrupts the normal sleep-wake cycle, causing individuals with narcolepsy to experience uncontrollable periods of sleep.

Understanding the role of orexin elucidates its importance in maintaining wakefulness and regulating sleep. In narcolepsy, the loss of orexin-producing neurons results in the inability to sustain alertness, thus directly linking this neurotransmitter to the disorder. This connection highlights the critical function of orexin in sleep regulation and its implications for sleep disorders.