Question

Describe how the hypothalamus regulates the function of the anterior and posterior pituitary differently. (Answer using complete sentences format only)

Answer 1

Answer

Anterior pituitary gland :

• Hypothalamus releases regulatory hormones (releasing and inhibiting hormones) that targets anterior pituitary gland and control its secretions.
  Example : TRH (Thyrotropin releasing hormone) from hypothalamus stimulates anterior pituitary gland to release TSH (Thyroid stimulating hormone).
• The hypothalamus and anterior pituitary gland connects via two capillary beds called hypothalamic–hypophysial portal system that facilitates transport of hypothalamic hormones to anterior pituitary gland.

Posterior pituitary gland :

• Hypothalamus and posterior pituitary gland are directly connected via hypothalamo-hypophyseal tract.
• It is a nerve tract having cell bodies in the hypothalamus and nerve endings in the posterior pituitary gland.
• This nerve tract passes through the pituitary stalk or infundibulum.
• Hypothalamus produced two hormones : Oxytocin and Anti-diuretic hormone that are stored in nerve endings located in the posterior pituitary gland.
• Upon stimulation, nerve impulse travel down the tract releasing these hormones from its secretory granules.
  Example : Osmoreceptos in hypothalamus sense increase fluid osmolarity. They stimulate posterior pituitary gland to release anti-diuretic hormone to conserve water and maintain homeostasis.