Relative density of hypocretin-immunoreactive fibers in various regions of the rat brain
| Brain region | Fiber density1-a |
|---|---|
| Cortex | |
| Layers 1–3 | ++ |
| Layer 4 | +(+) |
| Layers 5–6 | ++(+) |
| Olfactory bulb | |
| Main bulb | − |
| Anterior olfactory nuclei | + |
| Endopiriform nucleus | ++ |
| Claustrum | ++ |
| Tenia tecta | + |
| Hippocampus | + |
| Amygdala | |
| Amygdalohippocampal area | + |
| Anterior amygdaloid area | +++ |
| Basolateral nucleus | + |
| Basomedial nucleus | + |
| Cortical nucleus | + |
| Central nucleus | +++ |
| Intercalated nuclei | + |
| Lateral nucleus | + |
| Medial nucleus | ++ |
| Septum | |
| Lateral nucleus | +++ |
| Medial nucleus | +++ |
| Septofimbrial nucleus | ++ |
| Subfornical organ | − |
| Diagonal band of Broca | |
| Horizontal limb | ++ |
| Vertical limb | +++ |
| Bed nucleus of stria terminalis | |
| Lateral nucleus | +++ |
| Medial nucleus | +++ |
| Ventral nucleus | ++++ |
| Posteromedial nucleus | +++ |
| Posterolateral nucleus | ++++ |
| Basal ganglia | |
| Accumbens nucleus, core | + |
| Accumbens nucleus, shell | ++ |
| Caudate putamen | − |
| Globus pallidus | − |
| Fundus of the striatum | +++ |
| Thalamus | |
| Anteroventral thalamic nucleus | − |
| Anterior pretectal nucleus | − |
| Central medial nucleus | ++++ |
| Medial habenular nucleus | − |
| Mediodorsal thalamic nucleus | − |
| Lateral habenular nucleus | +++ |
| Laterodorsal nucleus | + |
| Paraventricular nucleus | ++++ |
| Reuniens nucleus | ++ |
| Rhomboid nucleus | ++ |
| Ventrolateral nucleus | − |
| Ventroposteriomedial nucleus | − |
| Ventroposteriolateral nucleus | − |
| Lateral geniculate nucleus | − |
| Medial geniculate nucleus | − |
| Zona incerta, rostral | ++++ |
| Zona incerta, caudal | ++ |
| Subincertal nucleus | ++++ |
| Subthalamic nucleus | ++++ |
| Subparafascicular thalamic nucleus | ++++ |
| Parafascicular nucleus | ++ |
| Central gray of the thalamus | ++++ |
| Anterior hypothalamus | |
| Medial preoptic area | +++ |
| Medial preoptic nucleus | ++ |
| Lateral preoptic nucleus | +++ |
| Magnocellular preoptic nucleus | +++ |
| Supraoptic nucleus | − |
| Suprachiasmatic nucleus | − |
| Anterior hypothalamic area, anterior part | ++ |
| Lateroanterior nucleus | +++ |
| Substantia innominata | ++++ |
| Ventral pallidum | +++ |
| Posterior hypothalamus | |
| Paraventricular nucleus | +++ |
| Ventromedial nucleus, rostral | ++ |
| Ventromedial nucleus, caudal | ++++ |
| Dorsomedial nucleus | ++++ |
| Dorsal hypothalamic area | ++++ |
| Lateral hypothalamic area | ++++ |
| Tuberum cinereum | ++++ |
| Tuberomammillary nucleus | ++++ |
| Perifornical nucleus | +++++ |
| Posterior hypothalamic area | ++++ |
| Arcuate nucleus | ++++ |
| Submammillary nucleus | ++++ |
| Mammillary bodies | − |
| Pineal gland | − |
| Midbrain | |
| Substantia nigra, compact part | ++++ |
| Substantia nigra, reticular part | − |
| Substantia nigra, lateral part | +++ |
| Ventral tegmental area | +++ |
| Central gray | ++++ |
| Red nucleus | − |
| Mesencephalic reticular formation | ++ |
| Interpeduncular nucleus | +++ |
| Brainstem | |
| Oculomotor nuclei | |
| Abducens nucleus (VI) | − |
| Oculomotor nucleus (III) | − |
| Trochlear motor nucleus (IV) | − |
| Trigeminal motor nucleus (V) | + |
| Facial motor nucleus (VII) | + |
| Motor nucleus of the vagus (X) | + |
| Hypoglossal nucleus (XII) | + |
| Somatosensory nuclei | |
| Superior colliculus | ++ |
| Inferior colliculus | ++ |
| Mesencephalic nucleus | − |
| Parabigeminal nucleus | + |
| Olivary nuclei | − |
| Cochlear nucleus, dorsal | ++ |
| Cochlear nucleus, ventral | − |
| Lateral lemniscus | +++ |
| Trapezoid body | − |
| Vestibular nuclei | ++ |
| Nucleus of the solitary tract | ++++ |
| Area postrema | ++ |
| Parabrachial nucleus | +++ |
| Kölliker-Fuse nucleus | +++ |
| Spinal trigeminal nucleus | − |
| Spinal trigeminal nucleus, gelatinous layer of the caudal part | +++ |
| Central gray nuclei | |
| Nucleus of Darkschwitsch | − |
| Anterior tegmental nucleus | + |
| Ventral tegmental nucleus | + |
| Dorsal tegmental nucleus | − |
| Laterodorsal tegmental nucleus | +++ |
| Barrington’s nucleus | +++ |
| Locus coeruleus | +++++ |
| Periaqueductal gray | ++++ |
| Raphe nuclei | |
| Raphe dorsalis | ++++ |
| Raphe median | +++ |
| Raphe magnus | ++++ |
| Raphe pallidus | ++ |
| Raphe obscurus | ++ |
| Raphe linearis | ++ |
| Raphe pontis | ++ |
| B9 | +++ |
| Reticular formation | |
| Central tegmental field | ++ |
| Pedunculopontine nucleus | +++ |
| Cuneiform nucleus | ++ |
| Parvocellular reticular area (and its α part) | +++ |
| Gigantocellular reticular area | ++ |
| Gigantocellular reticular area, α part | +++ |
| Gigantocellular reticular area, ventral part | ++++ |
| Dorsal paragigantocellular reticular area | ++ |
| Lateral paragigantocellular reticular area | +++ |
| Intermediate reticular field | +++ |
| Lateral reticular nucleus | + |
| Medullary reticular nuclei, dorsal part | ++++ |
| Medullary reticular nuclei, ventral part | ++ |
| Pontine nuclei (oral, ventral, and caudal) | + |
| Other brainstem nuclei | |
| Nucleus prepositus hypoglossi | ++ |
| Rostroventrolateral medulla | +++ |
| Caudoventrolateral medulla | ++ |
| Nucleus subcoeruleus (α, ventral, and dorsal) | ++ |
| Cerebellum (cortex and nuclei) | − |
| Ependyma | ++ |
↵F1-a Rating scale: +++++, greatest fiber density; +, lowest fiber density; and −, insignificant number of fibers.