Related Experiment Video

Updated: Aug 19, 2026

Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex
10:45

Simultaneous Electroencephalography, Real-time Measurement of Lactate Concentration and Optogenetic Manipulation of Neuronal Activity in the Rodent Cerebral Cortex

Published on: December 19, 2012

A commentary on the neurobiology of the hypocretin/orexin system

E Mignot1

  • 1Stanford Center for Narcolepsy, Department of Psychiatry and Behavioral Sciences, 1201 Welch Road, P-114, Palo Alto, CA 94305-5485, USA. mignot@stanford.edu

Neuropsychopharmacology : Official Publication of the American College of Neuropsychopharmacology
|October 30, 2001
PubMed

Insights

Hypocretins (also known as orexins) are key neurotransmitters regulating sleep and wakefulness. Dysfunction in this system is linked to narcolepsy and may influence appetite and energy balance.

Area of Science:

  • Neuroscience
  • Neuroendocrinology
  • Sleep Medicine

Background:

  • Hypocretins/orexins are emerging neurotransmitters with critical roles.
  • The system comprises two neuropeptides (Hcrt-1/OXA, Hcrt-2/OXB) and two receptors (Hcrtr1/OXR1, Hcrtr2/OXR2).
  • Hypocretin cells in the hypothalamus project widely, exerting excitatory effects.

Purpose of the Study:

  • To discuss the emerging functions of the hypocretin/orexin system.
  • To highlight its role in sleep regulation and narcolepsy.
  • To explore its potential involvement in appetite, energy metabolism, and psychiatric disorders.

Main Methods:

  • Review of existing literature on hypocretin/orexin system.
  • Analysis of hypocretin's role in sleep-wake cycles and narcolepsy.
  • Discussion of implications for appetite, energy metabolism, and psychiatry.

Main Results:

  • Hypocretin neurotransmission is crucial for maintaining wakefulness.
  • Alterations in this system cause narcolepsy across species.
  • The system influences appetite, energy metabolism, and neuroendocrine functions.

Conclusions:

  • The hypocretin/orexin system is vital for sleep-wake regulation.
  • It uniquely integrates sleep, appetite, and neuroendocrine control.
  • Further research is warranted for its role in psychiatric conditions and sleep deprivation.

More Related Videos

Optogenetic Manipulation of Neural Circuits During Monitoring Sleep/wakefulness States in Mice08:58

Optogenetic Manipulation of Neural Circuits During Monitoring Sleep/wakefulness States in Mice

Published on: June 19, 2019

Isolation of Targeted Hypothalamic Neurons for Studies of Hormonal, Metabolic, and Electrical Regulation09:29

Isolation of Targeted Hypothalamic Neurons for Studies of Hormonal, Metabolic, and Electrical Regulation

Published on: August 4, 2023

Related Concept Videos

Diencephalon: Anatomical Regions01:30

Diencephalon: Anatomical Regions

The diencephalon, etymologically translated as 'through brain,' plays an integral role as the conduit between the cerebrum and the vast extent of the nervous system. However, the olfactory system is an exception, as it interfaces directly with the cerebrum. The diencephalon, deeply ensconced beneath the cerebrum, primarily consists of three paired structures — the thalamus, hypothalamus, and epithelamus. It also includes accessory structures such as the subthalamus, which houses the subthalamic...
Diencephalon: Hypothalamus and Coordination01:23

Diencephalon: Hypothalamus and Coordination

The hypothalamus is a small yet highly complex and essential brain region that plays a crucial role in regulating various bodily functions. Anatomically, it is located at the base of the brain, just above the brainstem and below the thalamus, forming part of the limbic system.
The hypothalamus interacts with other brain regions, including the pituitary gland, through a direct physical connection called the hypothalamic-pituitary axis. The hypothalamus receives somatic and visceral inputs and...
Functional Brain Systems: Reticular Formation01:13

Functional Brain Systems: Reticular Formation

The reticular formation is a complex network of gray and white matter located within the brainstem extending from the medulla to the midbrain.
Within the reticular formation, there are several distinct nuclei that can be classified into three broad categories. The Raphe nuclei are located along the midline of the brainstem. They are primarily known for their role in synthesizing and releasing serotonin, a neurotransmitter involved in regulating mood, appetite, sleep, and circadian rhythms. The...
Sleep-Wake Cycles01:24

Sleep-Wake Cycles

Sleep is an essential physiological process vital to maintaining overall well-being. The reticular activating system (RAS), a network of neurons in the brainstem, regulates wakefulness and sleep. While it may seem passive, sleep consists of distinct cycles, each with its unique characteristics and functions. Two key sleep phases are non-rapid eye movement (NREM) and  rapid eye movement (REM).
NREM Sleep
NREM sleep comprises four progressive stages that seamlessly merge:
Regulation of Hormone Secretion01:19

Regulation of Hormone Secretion

Regulation of hormone secretion is a finely tuned orchestration driven by various types of stimuli, encompassing neural, humoral, and hormonal signals. Environmental cues instigate neural stimuli, where action potentials traverse nerve fibers to reach their designated targets. An illustrative scenario is the body's response to stress, wherein the sympathetic nervous system releases epinephrine from the adrenal glands, inducing the well-known 'fight or flight' reaction.
Humoral stimuli,...
Neurotransmitters01:31

Neurotransmitters

Neurotransmitters are essential chemical messengers within the nervous system, facilitating the communication between neurons. These chemical messengers, varying in function and effect, are critical for sustaining various aspects of neurological health and emotional well-being.