pituitary gland stuff

Question 1

pituitary lies below what in the brain

Answer 1

sella turcica

Question 2

what is the anterior lobe of the pituitary embryologically derived from

Answer 2

invagination of the roof of the embryonic oropharynx known as Rathke’s pouch

Question 3

What is the pituitary stalk formed from

Answer 3

notochordal projection

Question 4

Blood supply to pituitary gland

Answer 4

1) long and short pituitary arteries

2) from hypophyseal portal circulation - begins as capillary plexus around the Arc

Question 5

Anterior pituitary hormones

Answer 5

ACTH, TSH, GH, LH/FSH, PRL

Question 6

what is ACTH for

Answer 6

regulation of adrenal cortex

Question 7

what is PRL for

Answer 7

Breast milk production

Question 8

what is released from the posterior pituitary

Answer 8

ADH, oxytocin

Question 9

Clinical presentation of pituitary tumours

Answer 9

Hormone hypersecretion
SOL: headaches, visual field defect, cavernous sinus invasion
Hormone deficiency states: inference w/surrounding normal pituitary

Question 10

Syndromes of hormone excess caused by anterior pituitary tumours

Answer 10

Acromegaly, Cushing’s Disease, 2ry thyrotoxicosis, prolactinoma

Question 11

Effects of GH/IGF-1 excess

Answer 11

Acral enlargement, incl shoe size, macroglossia, carpal tunnel, increased skin thickness, sweating, visceral enlargement, metabolic changes, impaired fasting glucose, DM, reduced total cholesterol, increased triglycerides, nitrogen retention

Question 12

other consequence of GH/IGF-1 excess

Answer 12

cardiomyopathy
hypertension
bowel polyps
colonic cancer
multinodular goiter
hypogonadism
arthropathy
OSA

Question 13

Actions of cortisol

Answer 13

increased plasma glucose, lipolysis, protein catabolysis, sodium and water retention, anti inflammatory, increased gastric acid production

Question 14

3 general signs of cushings syndrome

Answer 14

changes in protein and fat metabolism changes in sex hormones salt and water retention

Question 15

how is PRL regulated

Answer 15

positive feedback - tonic release of DA inhibits PRL release

Question 16

Which types of drugs interfere with DA and PRL secretion

Answer 16

Antiemetics
Antipsychotics
OCP/HRT

Question 17

Features of PRL excess (hypogonadism)

Answer 17

Infertility
(Oligo)amenorrhoea
Reduced libido
Impotence

Question 18

Treatment of hypogonadism

Answer 18

bromocriptine/cabergoline

Question 19

non functioning pituitary tumours make up what proportion of all pituitary tumours

Answer 19

30%

Question 20

In non functioning pituitary tumours, no syndrome of hormone excess is produced. How do they cause symptoms?

Answer 20

Space occupation - headache, visual field defect, nerve palsies, interfere w/ rest of pituitary function - deficiency of hormones

Question 21

how are non functioning pituitary tumours treated

Answer 21

no effective medical therapy - surgery: transsphenoidal approach +/- radiotherapy

Question 22

how is pituitary function lost with tumour expansion

Answer 22

LH/FSH
GH
TSH
ACTH
Increased prolactin

Question 23

Treatment of pituitary adenomas

Answer 23

SURGERY: Transsphenoidal (adrenalectomy - Nelson’s syndrome)
RADIOTHERAPY - slow
DRUGS: block hormone production, stop hormone release

Question 24

Causes of pituitary failure

Answer 24

Tumour, trauma, infection, inflammation (sarcoidosis or histiocytosis), iatrogenic

Question 25

thyroid related symptoms of hypopituitarism

Answer 25

``` bradycardia weight gain cold intolerance hypothermia constipation ```

Question 26

sex steroid related symptoms of hypopituitarism

Answer 26

oligomenorrhoea reduced libido hot flushes reduced body hair

Question 27

reduced cortisol related symptoms of hypopituitarism

Answer 27

``` tiredness weakness anorexia postural hypotension myalgia ```

Question 28

symptoms reduced GH

Answer 28

tired, central weight gain

Question 29

Treatment for hypopituitarism

Answer 29

Thyroid - thyroxine Sex steroids - testosterone/oestrogen reduced cortisol - hydrocortisone reduced GH - growth hormone

Question 30

causes of syndrome of inappropriate ADH (SIADH)

Answer 30

too much ADH brain injury/infection lung cancer/infection asthma IPPV metabolic - hypothyroidism, addison's

Question 31

Diagnosis of SIADH

Answer 31

plasma Na+ 100mOsm/kg | urine Na >50mmol/L

Question 32

Treatment of SIADH

Answer 32

fluid restriction

Question 33

what is Diabetes insipidus

Answer 33

ADH underproduction Cranial: lack of production Nephrogenic: receptor resistance

Question 34

Diabetes insipidus diagnosis

Answer 34

polyuria >3L | polydipsia - increased Na and plasma osmolality, decreased urine osmolality and Na