Hypothalamus and Pituitary Gland
Learning Objectives:
- Describe the location and anatomy of the hypothalamus and pituitary.
- Explain the functional relationship between the two structures.
1. Introduction to the Hypothalamus
1.1. Major Hypothalamic Nuclei and Their Functions
Below is a summary of key hypothalamic nuclei, their locations, and functions:
|
Nucleus |
Region |
Main Functions |
|
Supraoptic |
Anterior |
Produces antidiuretic hormone (ADH) → transported to posterior pituitary |
|
Paraventricular |
Anterior |
Produces oxytocin and some ADH; regulates stress, metabolism, lactation |
|
Preoptic (Medial & Lateral) |
Anterior |
Thermoregulation (heat loss), sexual behavior, gonadotropin regulation |
|
Suprachiasmatic |
Anterior |
Biological clock – controls circadian rhythms via retinal input |
|
Arcuate |
Tuberal |
Regulates secretion of pituitary hormones via releasing/inhibiting hormones; involved in feeding |
|
Ventromedial |
Tuberal |
Satiety center – inhibits feeding; stimulation → stop eating |
|
Dorsomedial |
Tuberal |
Emotional behavior, autonomic regulation |
|
Posterior nucleus |
Posterior |
Heat conservation, sympathetic responses, arousal |
|
Mammillary nuclei |
Posterior |
Part of limbic system; involved in memory and learning via mammillothalamic tract |