T1 L1 pt 2 : Introduction to the Endocrine System

Question 1

what nuclei are oxytocin and ADH synthesised in the hypothalamus (1m)

Answer 1

they are synthesised in the Supraoptic and paraventricular nuclei

Question 2

where are oxytocin and ADH stored (1m)

Answer 2

the posterior pituitary gland

Question 3

what is the function of ADH ( 2 marks)

Answer 3

Stimulation of v2 receptors causes translocation of aquaporins to the membrane of the kidney tubule, thus allowing water reabsorption.

Question 4

what is the function of ADH on V1 receptors

and at what concentrations (2m)

Answer 4

it causes vasoconstriction- at abnormal concs

Question 5

what occurs if there is low blood volume

1m) -(what receptors are stimulated

Answer 5

stim of V1 receptors

Question 6

what system is stimulated if there is a decrease in blood pressure and what is effect
(2m)

Answer 6

stim of the angiotensin synthesis and increased thirst - increased fluid intake

Question 7

what is the function of oxytocin (3m)

Incl- how it acts, what secretion is stim by, and what processes its important for

Answer 7

Oxytocin acts via IP3 to cause contraction of the smooth muscle of the genital tract (uterus) and breast.

Secretion of oxytocin is stimulated by stimulation of the genitals and nipples.

Oxytocin is most important at parturition and during lactation

Question 8

what hormone causes milk let down (1m)

Answer 8

Oxytocin

Question 9

describe the mechanisms of action for oxytocin in the (2m)

Answer 9

G-protein linked receptor, calcium infux, -1 -contraction of myometrium, increased stim of strtch receptors on uterine wall, expulsion of the foetus.

2- contraction of smooth muscle of the myoepithelium and milk let down

Question 10

name some hormones secreted by the anterior pituitary gland

5m

Answer 10

Growth Hormone

Prolactin

Thyroid Stimulating Hormone

Adrenocorticotrophic Hormone

Follicle stimulating Hormone

Luteinising Hormone

Question 11

what cells synthesize the TSH

Answer 11

Thyrotrophe cells

Question 12

what cells synthesize ACTH

Answer 12

corticotrophe cells

Question 13

what cells synthesize FSH

Answer 13

gonadotrophe cells

Question 14

what does GHRH stimulate the secretion of

Answer 14

Growth hormone

Question 15

where do the releasing hormones travel through

Answer 15

The hypothalamico-hypophyseal portal vessel

Question 16

what hormones are tested for

Answer 16

TSH & FT4  
Cortisol
LH & FSH
Prl
Testosterone / “Periods”

Question 17

what is done after biochemical tests

Answer 17

Imaging

Question 18

what tests can be done for the eyes

Answer 18

the visual field tests

Question 19

what can cause compression of the optic chiasm

Answer 19

enlargement of the pituitary gland

Question 20

what can enlargement of the pituitary gland cause

Answer 20

Bilateral hemianopsia

Question 21

what stimulates prolactin synthesis

Answer 21

TRH

Question 22

give an example of a prolactin release inhibiting factor

Answer 22

Dopamine

Question 23

what is prolactin secretion stimulated by

Answer 23

Mild stress
Nipple stimulation
Coitus

Question 24

what is the function of prolactin

Answer 24

promote lactation, and development of breast tissue.

It is most important in females after puberty and during and after pregnancy

Question 25

what cells is the growth hormone secreted in

Answer 25

the somatotrophe cells

Question 26

what inhibits GH

Answer 26

(GHRIH)

somatostatin

Question 27

what is the secretion of the growth hormone stimulated by

Answer 27

decreased carbohydrates and fatty acids and increased amino acids.

Question 28

what does the GH stimulate in the liver

Answer 28

the release of secondary messengers such as Insulin-like growth factor 1 & 2

Question 29

what is the growth hormones 3 main functions

Answer 29

protein synthesis and collagen deposition
&
tissue turnover and repair.