The Pituitary Gland

Question 1

What are some key integrative functions of the hypothalamus and pituitary?

Answer 1

Question 2

What kinds of hormones does the hypothalamus release?

Answer 2

Neurohormones

Question 3

What kind of hormones does the posterior pituitary release?

Answer 3

Neurohormones (from hypothalamus)

Question 4

What kind of hormones does the anterior pituitary release?

Answer 4

Endocrine hormones

Question 5

What are 5 examples of tropic hypothalamic hormones?

Answer 5

Thyrotropic releasing hormone (TRH)

Corticotropin releasing hormone (CRH)

Growth hormone releasing hormone (GHRH)

Gonadotropin releasing hormone (GRH)

Prolactin releasing hormone (PRH)

Question 6

What are 2 inhibiting tropic hypothalamic hormones?

Answer 6

Growth hormone inhibiting hormone (GHIH)

Dopamine

Question 7

What is dopamine also known as?

Answer 7

Prolactin inhibiting hormone (PIH)

Question 8

What is the classification of all of the tropic hypothalamic hormones?

Answer 8

Peptides, except for dopamine which is an amine

Question 9

How are hormones transfered from hypothalamus to anterior pituitary?

Answer 9

Through hypothalamo-hypophyseal portal system (network of tiny vessels)

Question 10

Contrast the anterior and posterior pituitary in terms of:

type of tissue

connections via

also called

size

Answer 10

Question 11

Is the anterior or posterior pituitary larger?

Answer 11

Anterior makes up 2/3 of gland, posterior 1/3

Question 12

What are the 6 hormones released by the anterior pituitary gland?

Answer 12

Thyroid stimulating hormone (TSH)

Adrenocorticotrophic hormone (ACTH)

Follicle stimulating hormone (FSH)

Luteinising hormone (LH)

Growth hormone (GH)

Prolactin

Question 13

What is the classification of anterior pituitary hormones?

Answer 13

All are peptides, and 5 are also tropic hormones

Question 14

What does prolactin do?

Answer 14

Stimulates milk production from the breast during lactation

Question 15

What is the target organ of prolacin?

Answer 15

Mammary glands

Question 16

What is the target organ of GH?

Answer 16

Musculoskeletal system

Question 17

What is the target organ of TSH

Answer 17

Thyroid gland

Question 18

What is the target organ of ACTH?

Answer 18

Adrenal cortex

Question 19

What is the target organ of gonadotropins?

Answer 19

Gonads (ovary/testes)

Question 20

What does TSH cause?

Answer 20

Thyroid hormone (TH) release from thyroid

Question 21

What does addrenocorticotropic hormone cause?

Answer 21

Cortisol release from adrenal cortex

Question 22

What tropic and what direct effects does GH have?

Answer 22

Tropic - IGF-1 release from liver

Direct - tissue metabolism

Question 23

What tropic and what direct effect does luteinising hormone have?

Answer 23

Tropic - sex hormone release

Direct - regulation of reproductive function

Question 24

What are the 3 integration centres involved in the feedback control of the anterior pituitary?

Answer 24

Hypothalamus

Anterior pituitary

Target endocrine cell

Question 25

What are the 2 neurohormones stored and released from the posterior pituitary?

Answer 25

Vasopressin

Oxytocin

Question 26

Are the hormones released from the posterior pituitary formed there?

Answer 26

No, they are formed in the hypothalamus but stored and released fromt he posterior pituitary

Question 27

What are vasopressin and oxytocin synthesised in?

Answer 27

Magnocellular neurones in hypothalamus

Question 28

How does vasopressin and oxytocin get from hypothalamus to posterior pituitary?

Answer 28

1) Axons project down infundibulim to posterior pituitary
2) Do not synapse with other neurons, terminals end directly on capillaries

Question 29

What classification of hormones do posterior pituitary hormones behave as?

Answer 29

Typical peptide hormones, so:

synthesis and storage in vesicles

acts on cell surface receptors

Question 30

For Vasopressin and Oxcytocin compare the:

• Function
• Trigger
• Mode of action

Answer 30