Pharmacology--Endocrine And Pituitary

Front 1

What are three uses for agents that affect endocrine function?

Back 1

1) to analyse the functional integrity of endocrine control systems-->diagnostic tests-->ex: somatotrophin test for GH responsiveness

2) as replacements in hormone deficiency states-->ex: thyroid hormone for hypothyroidism

3) to modify endocrine system function-->ex: dopamine agonists for hyperprolactinaemia, oral contraception

Front 2

How do agents influence endocrine systems?

Back 2

1) mimic or block the actions of endogenous hormones-->agonists in the absence of endogenous hormones, antagonists in the presence of excess endogenous hormones

2) interfere with regulation pathways-->increase/decrease endogenous hormone levels

Front 3

Which hormones are made/released by the hypothalamus? (9)

Back 3

1) dopamine

2) VIP

3) TRH

4) somatostatin

5) GRH dopamine

6) GnRH

7) CRH

8) vasopressin

9) oxytocin

Front 4

What hormones are released by the anterior pituitary? (6)

Back 4

1) PRL

2) TSH

3) GH

4) FSH

5) LH

6) ACTH

Front 5

Which hormones are stored and released by the posterior pituitary? (2)

Back 5

1) vasopressin

2) oxytocin

Front 6

What are the 3 vasopressin receptors and what do they do in the end?

Back 6

V1A-->vasoconstriction

V1B--> ACTH release

V2-->water reabsorption in DCT and CT

Front 7

What is the oxytocin receptor and how does it work in the end?

Back 7

OT-->inhibits AC

Front 8

What are the actions of oxytocin?

Back 8

contracts the smooth muscle of the uterus

causes milk release during lactation

positive social interactions

enhances social contract and promotes social cohesion

Front 9

What are the actions of vasopressin/ADH and when is it released?

Back 9

control of body water

released in response to change in blood osmolality

Front 10

What is diabetes insipidus?

Back 10

vasopressin (ADH) deficiency

Front 11

What are the symptoms of diabetes insipidus?

Back 11

thirst

polydipsia

polyuria

Front 12

What is pituitary diabetes insipidus due to?

Back 12

due to decreased vasopressin

Front 13

What is neurogenic diabetes insipidus due to?

Back 13

due to decreased vasopressin

Front 14

What is nephrogenic diabetes insipidus?

Back 14

due to decreased response to vasopressin

Front 15

How is pituitary diabetes insipidus treated?

Back 15

with vasopressin or analogues

vasopressin

desmopressin

Front 16

What is desmopressin selective for?

What is it a potential use for it?

Back 16

V2 receptors

nocturnal enuresis

Front 17

What is vasopressin (ADH) excess caused by and how is it treated?

Back 17

due to small cell carcinoma in the lung-->ectopic vasopressin secretion

hypertension and fluid retention

treat with V-receptor antagonists

Front 18

What are V2 agonists associated with?

Back 18

increased water reabsorption

Front 19

What are V1A receptor agonists associated with?

Back 19

vasoconstriction

Front 20

What are V1A and V1B receptor agonists associated with?

Back 20

behavioural and endocrine responses to stress and anxiety

Front 21

What are prolactin receptors linked to? (enzyme)

Back 21

tyrosine kinase-linked

Front 22

What hormones can enhance prolactin release?

Back 22

TRH

VIP-->Vasoactive intestinal peptide

oxytocin

Front 23

What hormone does prolactin suppress?

Back 23

supresses estrogen synthesis

decreased GnRH

Front 24

What causes prolactin hyper secretion?

Back 24

DA antagonists-->classic antipsychotic agents

hypothyroidism-->due to increased TRH

pituitary tumors-->lactotrophic cells

Front 25

What symptoms does prolactin hyper secretion cause?

Back 25

infertility

galactorrhea

Front 26

How is prolactin excess treated?

Back 26

dopamin receptor agonists-->can shrink pituitary lactotroph adenomas

Front 27

ADRs of dopamine receptor agoinsts

Back 27

nausea & vomiting

dizziness, postural hypotension

tolerance develops to side-effects but not to the therapeutic effect

Front 28

What are growth hormone (somatotrophin) receptors linked to?

Back 28

tyrosine kinase

Front 29

How does somatotrophin (GH) work?

Back 29

increases IGF-1 (somatomedin) to mediate anabolic effects

Front 30

What stimulates GH release?

Back 30

GHRH (somatorelin)

Front 31

What inhibits GH release?

Back 31

GHIH (somatostatin)

Front 32

What other factors causes growth hormone (somatotrophin) release?

Back 32

exercise

stress

hypoglycemia

Front 33

What are some possible causes of growth hormone deficiency?

Back 33

hypopituitarism

selective impairments of somatotrophs

deficient GHRH release

Front 34

What are the consequences of growth hormone (somatotrophin) deficiencies in children and adults?

Back 34

children--short stature

adults-->wasting--> increased body fat, decreased muscle mass, decreased BMD

Front 35

What are the treatments for growth hormone (somatotrophin) deficiency?

Back 35

pituitary extracts

recombinant human GH (rhGH)

somatropin (synthetic hGH)

Front 36

What are the effects of somatropin (hGH)?

Back 36

growth promoting effects-->promotes growth of skeletal, muscular and other tissues

anabolic effects-->stimulates protein anabolism and influences fat and mineral metabolism

Front 37

ADRs of somatropin

Back 37

muscle pain

joint pain

MS stiffness

local reactions, lipoatrophy

peripheral edema

hypothyroidism

Front 38

What are GH releasing factors used for?

Back 38

analogues

diagnostic test for GH release

potentially anti-ageing therapy

HIV-related lipodystrophy

Front 39

What is the common cause of growth hormone excess?

Back 39

adenoma

Front 40

What does excess GH cause in children and adults?

Back 40

children-->giantism

adults-->acromegaly

Front 41

What is the treatment of acromegaly?

Back 41

aim is to normalise GH and IGF levels

surgery usually 1st option-->removal or debulking

Drugs-->DA receptor agonists, somatostatin analogues, GH receptor antagonist

Front 42

What are some pros and cons to DA receptor agonists in the treatment of acromegaly?

Back 42

cheapest option

only 20% of patients respond

normalises GH secretion in these patients

ADR profile is problematic

Front 43

What are some pros and cons to somatostatin analogues?

Back 43

longer actiing

supresison test may be used to see if respond

can cause hypothyroidism

Front 44

ADRs somatostatin analogues

Back 44

injection site reactions

headache

dizziness

GI upset

hypothyroidsism due to low TSH

Front 45

What do GH receptor antagonists do?

Back 45

do not decrease gH levels or tumour size

stops GH effects on target tissues

Front 46

ADRS

GH receptor antagonist

Back 46

injection site reactions

swollen limbs

chest pain

hypoglycaemia