The Pituitary Gland

Question 1

What are the routes of communication within the hypothalamus-pituitary gland complex?

Answer 1

Neural communication – posterior pituitary is connected to the hypothalamus with neural tissue

Endocrine communication - anterior pituitary is connected to hypothalamus and is a true endocrine gland.

The hypothalamo-hypophyseal portal system is a network of tiny vessels which transport trophic hormones from hypothalamus to the anterior pituitary.

The trophic hormones are released from the neurosecretory neurons at the median eminence

These hormones travel a very short distance, so they act very quickly.

Question 2

What do the following terms mean?

Troph

Trophic hormone

Hypophysiotrophic hormone

Answer 2

Troph - stimulating the activity of another endocrine gland

Trophic hormone - A hormone which stimulates the release of another hormone

Hypophysiotrophic hormone - These are hormones which are produced by the hypothalamus and travel into the anterior pituitary via the median eminence.

Question 3

What hormones are produced by the Anterior Pituitary?

Answer 3

• TSH
• ACTH
• FSH
• LH
• GH
• Prolactin (not trophic)

Question 4

What hormones are produced by the hypothalamus?

Answer 4

• Thyrotrophin releasing hormone
• Corticotrophin releasing hormone
• Growth Hormone releasing hormone
• Gonadotrophin releasing hormone
• Prolactin releasing hormone
• Prolactin inhibiting hormone
• Growth hormone inhibiting hormone

Question 5

What hormones are produced by the posterior pituitary?

Answer 5

• ADH (peptide)
• Oxytocin (peptide)