Table 1.

Relative density of hypocretin-immunoreactive fibers in various regions of the rat brain

Brain regionFiber 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.