hypothalamus axis

Question 1

what is the posterior lobe made out of

Answer 1

The posterior lobe is made of nerve endings coming from
specific hypothalamic neurones, and glial-like cells

Question 2

what is vasopressin

Answer 2

VP also causes vasoconstriction (via V1 receptors), platelet
aggregation and mobilisation of coagulation factor.

Question 3

what is oxytocin

Answer 3

Nonapeptide, stimulates contraction of the uterus during
labour and contraction of contractile cells

Question 4

what is the therapeutic use of oxytocin

Answer 4

to stimulate contraction during delivery
(overdose very dangerous), to assist breastfeeding, to reduce post-partum or miscarriage
bleeding, late therapeutic abortion.

Question 5

what can oxytoxin help with

Answer 5

weight loss
decreased anxiety
improved sleep
better sex

Question 6

what are 4 tropic hormones

Answer 6

TSH ACTH LH FSH

Question 7

WHAT IS TSH

Answer 7

stimulates thyroid gland and secretion of Thyroid hormones

Question 8

WHAT IS ACTH

Answer 8

Stimulates adrenal cortex and the secretion of glucocorticoids

Question 9

WHAT IS LH

Answer 9

stimulate secretion of oestrogens by the
ovaries and secretion of testosterone by the testes, regulate
menstrual cycle.

Question 10

WHAT IS FSH

Answer 10

stimulate secretion of oestrogens by the
ovaries and secretion of testosterone by the testes, regulate
menstrual cycle.

Question 11

WHAT IS PRL

Answer 11

Prolactin initiates milk production and
development of mammary gland.

Question 12

WHAT IS GH

Answer 12

Growth hormone, (somatotropin ) controls general
body growth, increases protein synthesis, cell proliferation and
bone growth, metabolic effects, induces the release of IGF
(insulin like growth factor) from liver.

Question 13

WHAT IS a-MSH:

Answer 13

Melanocyte-stimulating hormone, synthesised
from the same precursor than ACTH, some effects on skin
pigmentation. In the brain MSH neurons regulate appetite

Question 14

WHAT ARE HYPOTHALAMAUS FACTORS

Answer 14

TRH
GNRH
GNRH
GHIH
CRH
DOPAMINE

Question 15

WHAT IS TRH

Answer 15

Thyrotropin releasing hormone (tripeptide), stimulates the release
of TSH from the thyrotroph cells

Question 16

WHAT IS GNRH

Answer 16

Gonadotropin releasing hormone, stimulates the release of the
gonadotropins LH and FSH from the gonadotroph cells

Question 17

WHAT IS GHRH

Answer 17

Growth hormone releasing hormone (GHRH), stimulates the
release of growth hormone from the somatotroph cells

Question 18

WHAT IS GHIH

Answer 18

Growth hormone inhibitory hormone (GHIH), or somatostatin,
inhibits the release of growth hormone

Question 19

WHAT IS CRH

Answer 19

Corticotropin releasing hormone, stimulates the release of ACTH
from the corticotroph cells

Question 20

WHAT ARE 4 CHARACTERISTICS OF HYPOTHALMIC RELEASING FACTORS

Answer 20

release dependant on neuronal impulse
* secretion is pulsatile (1 pulse/60-180 min)
* regulated by the feed back of secreted hormones or other
upstream components
* relatively small peptides (except dopamine!)

Question 21

WHAT DOES TOTAL DEFICIENCY OF GROWTH HORMONES CAUSE

Answer 21

PITUATARY DWARFISM

Question 22

WHAT DOES PARTIAL DEFICIENCY OF GROWTH HORMONES CAUSE

Answer 22

GROWTH RETARDATION

Question 23

WHAT IS THE TREATMENT OF GROWTH DEFICIENCY

Answer 23

GH recombinant, like humatrope, protropin
(treatment very expensive), also used to treat
Turner’syndrome.

Question 24

WHAT DOES HYPERSECRETION CAUSE

Answer 24

Acromegaly (adults), rare, enlargement of
extremities, soft tissues swelling;
Giantism (children), very rare

Question 25

HOW IS HYPERSECRETION OF GROWTH HORMONES TREATED

Answer 25

ablation of the tumour and
somatostatin analogue (octeotride)

Question 26

WHAT IS THE ACTION OF PROLACTIN

Answer 26

Growth during puberty
and pregnancy, stimulate milk synthesis

Question 27

WHAT IS HYPERPROLACTINAEMIA

Answer 27

Growth during puberty
and pregnancy, stimulate milk synthesis

Question 28

WHAT ARE THE CAUSES OF HYPERPROLACTINAEMIA

Answer 28

PREGNANCY
TUMOURS
CONTRACEPTION WITHDRAWAL

Question 29

WHAT IS THE HYPOTHALMIC FACTOR OF THE Hypothalamo-pituitary-adrenal axis

Answer 29

CRH, stimulates release of ACTH from corticotroph cells.

Secretion negatively modulated by cortisol.
Pulsatile secretions which drive secretions of ACTH and consequently
cortisol.

Highest peak at early morning hypersecretion in major
depression.

Question 30

WHAT IS THE PITUITARY HORMONE RELEASED BY THE Hypothalamo-pituitary-adrenal axis

Answer 30

acth

Question 31

what is the hypothalmic factor in the Hypothalamo-pituitary-thyroid axis

Answer 31

TRH

tripeptide, pulsatile secretion,
activate of TSH from pituitary.

Secretion inhibited by thyroid hormone and stimulated by cold
exposure (negative feedback overridden during cold exposure),
suckling, , stress, inhibited by fasting.

Question 32

what is the pituatry hormone released by the Hypothalamo-pituitary-thyroid axis

Answer 32

TSH

Question 33

what is precocious puberty

Answer 33

hyper secretion of LH FSH

Question 34

what is the treatment of precorcious puberty

Answer 34

GnRH agonists are prescribed
eg leuprorelin, nafarelin also given in fertility treatment)

Question 35

what is the target of tsh

Answer 35

thryoid gland

Question 36

what is the pathology of tsh

Answer 36

Excessive secretion
in most cases of
hypothyroidism

Question 37

what is the pathology of acth

Answer 37

Excessive secretion in
Cushing’s disease
(tumour of corticotroph)

Question 38

what is the pathology of lh and fsh

Answer 38

Excessive secretion in
Precocious puberty (due to
abnormal secretion of
GnRH)

Question 39

what is the pathology of prolactin

Answer 39

Excessive secretion in
Gynecomastia, Galactorrea

Question 40

what is the pathology of growth hormones

Answer 40

Excessive secretion in
acromegaly, gigantism
Absence of secretion in
pituitary dwarfism