hypothalamus

Function

• autonomic nervous system
• endocrine system
  • secretion of releasing hormones which travel through the pituitary stalk to the anterior pituitary to stimulate release of anterior pituitary hormones (in parentheses)
    • corticotropin-releasing hormone (ACTH)
    • gonadotropin-releasing hormone (FSH & LH)
    • thyrotropin-releasing hormone (TSH)
    • growth hormone-releasing hormone (GH)
  • efferents from the supraoptic nucleus & the paraventricular nucleus travel through the pituitary stalk to synapse in the posterior pituitary facilitating secretion of oyxtocin & vasopressin
• regulation of mood
• motivation
• satiety
• temperature regulation (site of thermoregulatory center)

Structure

• the ventral & medial region of the diencephalon forming the walls of the ventral 1/2 of the 3rd ventricle
• it is delineated from the thalamus by the hypothalamic sulcus
• it lies medially to the internal capsule on either side
• it is continuous with the pre-commissural septum anteriorly & with the mesencephalic tegmentum & periaqueductal gray matter posteriorly
• on its ventral surface is the optic chiasm, the infundibulum that extends to the posterior lobe of the pituitary by its stalk & the paired mammillary bodies.

The hypothalamus consists 5 areas, each containing specific nuclei:

• anterior area
• dorsal area
• intermediate area
• lateral area
• posterior area

Afferents

• mesencephalon (midbrain)
• limbic system
• cerebellum
• also under endocrine influence

Efferents

• mesencephalon (midbrain)
• limbic system
• cerebellum
• posterior pituitary
• a functional (endocrine) connection with the anterior pituitary via the hypothalamic-pituitary portal system

Pathology

• hypothlaamus may play a role in regulation of aging through NF-kappaB, IKK & GnRH-regulated pathways implicated in inflammation

More general terms

• brain structure

Additional terms

• anterior pituitary (adenohypophysis)
• hypothalamic-pituitary-portal circulation
• posterior pituitary (neurohypophysis)

Component of

• diencephalon
• limbic system

Components

• tuberomammillary nucleus
• tuber cinereum
• median eminence of hypothalamus
• hypothalamus posterior
• hypothalamus lateral
• hypothalamus middle
• hypothalamus anterior