Hormones & Signal Transduction 5 Sections28 LessonsLifetime
Hypothalamus & Pituitary
Hypothalamic & Pituitary hormones
Hypothalamus
The Paraventricular Nucleus (PVN), located in the anterior medial area of hypothalamus, is involved in the release of oxytocin and vasopressin from the pituitary.
The Arcuate Nucleus (ARC) is involved in secretion of various pituitary releasing hormones.
The Dorsomedial Hypothalamic nucleus (DMH) is involved in stimulating gastrointestinal activity.
The Ventromedial Nucleus (VMN) is involved in satiety.
The overall function of the hypothalamus is to link the CNS to the endocrine system via the pituitary gland (the hypophysis).
Hypothalamic & Pituitary hormones - Endocrine control
Anterior Pituitary
Hypothalamus → Pituitary
- GnRH → FSH
- CRH → ACTH
- TRH → TSH
- GHRH → GH
- PIF → Prolactin inhibition
Posterior Pituitary
- ADH-Antidiuretic Hormone (Vasopressin)
- Oxytocin
Hypothalamic & Pituitary Hormones
Hypothalamus produces 2 types of endocrine factors:
- Hypothalamic neuropeptides
- Hypothalamic releasing factors
1. Hypothalamic Neuropeptides
Produced by the supraoptic and paraventricular nuclei (hypothalamus)
These neurohormones are:
- Antidiuretic Hormone (ADH)
- Oxytocin.
* the precursors are long polypeptides
They are synthesized in hypothalamus.
Cleaved into the active molecule, and
Transported to posterior pituitary & stored there.
These are classified as Hormones of Posterior pituitary.
They are released to bloodstream by exocytosis.
2. Hypothalamic releasing factors
The releasing factors are neurosecretions synthesized in the hypothalamus and released through the hypothalamic pituitary portal circulation.
They affect the secretion of pituitary tropic hormone.