The Pituitary Gland

Question 1

What is the principle organising system of the endocrine system?

Answer 1

The Hypothalamus-Pituitary axis

Question 2

What is the hypothalamus-pituitary axis made of?

Answer 2

The hypothalamus connected to the pituitary gland via the infidibulum (stalk) - communication is both neural and endocrine

Question 3

Where do all hypothalamic trophic hormones bind to?

Answer 3

Receptors on the anterior pituitary

Question 4

What are the five essential stimulating hypothalamic ‘releasing’ hormones?

Answer 4

1. TRH
2. CRH
3. GHRH
4. GnRH
5. PRH

Question 5

What are the two hypothalamic inhibiting hormones?

Answer 5

1. Growth Hormone Inhibiting Hormone (Somatostatin)

2. Dopamine (Prolactin inhibiting hormone)

Question 6

What type of hormones are the hypothalamic inhibiting and releasing hormones>

Answer 6

All peptides except dopamine (amine)

Question 7

What are the functions of the two lobes of the pituitary gland?

Answer 7

Anterior - true endocrine gland

Posterior - Neuroendocrine gland

Question 8

What proportion of the pituitary gland is taken up by its anterior lobe?

Answer 8

2/3rds

Question 9

What hormones does the adenohypophysis (anterior lobe) secrete?

Answer 9

1. TSH
2. ACTH
   3 FSH
3. LH
4. GH
5. ProL

Question 10

What three centres integrate to form a complex control system for the anterior pituitary?

Answer 10

1. Hypothalamus
2. Anterior pituitary
3. Target endocrine cell

Question 11

What is a short feedback loop for the anterior pituitary?

Answer 11

Where the hormone produced by the AP is an inhibiting molecule for the hypothalamus

Question 12

What is a long feedback loop for the anterior pituitary?

Answer 12

Where the hormone produced by the pituitary’s target organ acts as an inhibiting molecule for the pituitary/hypothalamus

Question 13

What two peptide hormones does the posterior pituitary gland release?

Answer 13

Vasopressin and oxytocin

Question 14

How are vasopressin and oxytocin produced?

Answer 14

Synthesised in magnocellular neurones which have their cell bodies in specific areas of the hypothalamus

Question 15

How does the hypothalamus connect to the posterior pituitary?

Answer 15

Axons project down the infidibulum and into the PP

Question 16

What other characteristics do the hypothalamo-posterior pituitary axons have?

Answer 16

They do not synapse

They terminate directly on the capillary network

Question 17

What is the other name for the posterior pituitary?

Answer 17

Neurohypophysis

Question 18

What is the hypothalamus-hypophyseal portal system?

Answer 18

Network of tiny vessels which transfer trophic hormones from the hypothalamus to the anterior pituitary

Question 19

Where do nreuroecretory neurones release hormones?

Answer 19

Medial eminence

Question 20

What are trophic hormones?

Answer 20

Hormones which govern the release of other hormones

Question 21

What type of hormones are all hormones released from the hypothalamus?

Answer 21

Neurohormones

Question 22

What type of hormones are all hormones released by the posterior pituitary?

Answer 22

Neurohormones