T1 L3 p2 :The Nuts and Bolts of the Endocrine System: Anatomy and Histology Roadshow

Question 1

what is endocrine

Answer 1

Action of the hormone on a target organ away from the secreting cell

Question 2

what is autocrine

Answer 2

• Action of the hormone on the secreting cell

Question 3

what is paracrine

Answer 3

Action of the hormone on the adjacent cell

Question 4

Neuroendocrine

Answer 4

Neural stimulation of endocrine cells to secrete hormones e.g. the medulla of adrenal gland

Question 5

what are the clinical manifestations of endocrine diseases

Answer 5

Hormone overproduction

Hormone underproduction

Tumour/mass lesion which can be:
Non-functional → pressure effect
Associated over production of hormones

Question 6

What is the pituitary gland divided into

Answer 6

Adenohypophysis/anterior lobe

Neurohypophysis/posterior lobe

Question 7

what are the cells of the anterior pituitary gland

Answer 7

Acidophils – take up the acidic dyes

Basophils – take up the basic dyes

Chromophobe – no specific staining features

Question 8

look at slide number 10

Answer 8

look at it

Question 9

what hormones and targets are produced by these cells pituitary gland

1) Somatotroph
2) Lactotroph
3) Corticotroph
4) Gonadotroph
5) Thydrotroph

Answer 9

1) Growth Hormone - Bones
2) Prolactin - Breasts
3) Adrenocorticotrophic hormone (ACTH) -Adrenal glands

4)Follicle stimulating- Ovary & testis
hormone (FSH)
Luteinising hormone Ovary & testis
(LH)

5)Thyroid stimulating
(TSH)

Thyroid gland
			hormone

Question 10

what hormones are secreted from the posterior pituitary and what are their functions (2m)

Answer 10

1) Antidiuretic hormone (ADH) facilitates the absorption of water in kidneys which concentrates the urine
2) Oxytocin promotes contractions of the smooth muscle in the uterus during childbirth and myoepithelial cells in the breast during breast feeding-milk let down-milk ejection

Question 11

where does pituitary gland pathology occur

Answer 11

the adenohypophysis

Question 12

what do productive adenomas cause

Answer 12

hyperpituitarism

Question 13

what does excess pressure cause in the pituitary gland

Answer 13

hypopituitarism

Question 14

adenomas can be functioning or non-functioning

Answer 14

creating headaches vomiting and nausea

Question 15

when optic chiasma is compressed by the tumour what happens

Answer 15

Bitemporal hemianopsia

Question 16

what is the thyroid gland responsible for the synthesis off

Answer 16

T3- triiodothyronine

T4- thyroxine

Question 17

what causes an enlargened goitre

Answer 17

Lack of iodine as gland enlarges to absorb the max conc of iodine

Question 18

what do the follicles of the thyroid contain

Answer 18

Colloid - has eosinophilic (pink ) appearance

Question 19

where are Para-follicular cells-C cells found

Answer 19

they are found between follicles

Question 20

what do C cells secrete

Answer 20

Calcitonin which promotes reduction of calcium concentration in the blood

Question 21

what tests verify hyperthyroidism

Answer 21

elevated T4 and T3 level and a decreased TSH level

Question 22

what tests verify a hypothyroidism

Answer 22

elevated TSH level and a decreased T3 and T4 level

Question 23

What does Goitre have

Answer 23

euthyroid

Question 24

Graves disease is

Answer 24

Hyperthyroid

Question 25

Hashimoto's disease is

Answer 25

Hypothyroid

Question 26

Adenoma and cancer is

Answer 26

Euthyroid

Question 27

describe the process of forming a multi-nodular goitre

Answer 27

Lack of iodine leads to an enlarged thyroid gland termed goitre due to hyperplasia and hypertrophy of the thyroid cells The gland enlarges to maximise amount of iodine absorbed The increase in size overcomes the hormone deficiency and the patients are euthyroid

Question 28

what is a secondary effect of a successful thyroidectomy and why

Answer 28

Tracheomalacia - due to compression of the airways

Question 29

Graves disease (what causes it and what are the 2 effects in different organs) (5m)

Answer 29

Auto-antibodies stimulate TSH receptors Diffuse enlargement of the thyroid gland – goitre due to hyperplasia of thyroid cells Infiltrative opthalmopathy – accumulation of soft tissue and inflammatory cells behind the eye leading to proptosis Infiltrative dermopathy – thickening and induration of the skin on the anterior shin→ pre-tibial myxoedema

Question 30

what is Hashimoto's thyroiditis

Answer 30

It's the most common cause of hyporthyroidism in an area where iodine is readily available An autoimmune disease characterised by high TSH and low T3/T4

Question 31

what white cell infiltrates when hashimotos disease is prominent

Answer 31

Lymphocytes

Question 32

what cells have tumurs in the thyroid gland

Answer 32

Follicular cells- creating follicular adenomas

Question 33

what are the 4 main types of carcinomas

Answer 33

Papillary ( 75-85%); ↑ risk of lymph node metastasis Follicular (10-20%); ↑ Mets to bone, lung and liver Medullary (5%); arises from C cells ; 20% ass with MEN 2 syndrome (multiple endocrine neoplasm) Anaplastic (<5%); older patients; poor prognosis

Question 34

what is the function of para-follicular cells

Answer 34

C cells secrete calcitonin which promotes reduction of calcium concentration in the blood Para-follicular cells or clear cells (C cells) are found between the follicles C cells are the origin of medullary carcinoma of the thyroid

Question 35

what are parathyroid glands

Answer 35

they secrete parathyroid hormones -PTH they control the levels of calcium in the blood low ca stims PTH secretion Chief cells with no lumen

Question 36

what pathology involves one parathyroid one gland

Answer 36

Adenoma

Question 37

what pathology involves all 4 glands

Answer 37

Hyperplasia

Question 38

which pathologies cause hypercalcaemia

Answer 38

Adenomas and hyperplasia

Question 39

what are the 3 zones of the adrenal gland

Answer 39

Glomerulosa fasciculata reticularis

Question 40

what does the glomerulosa produce

Answer 40

- Mineralocorticoid - Aldosterone - For absorption of sodium

Question 41

what does the fasciculata

Answer 41

- Glucocorticoids - Cortisol & corticosterone - Sex hormones

Question 42

Zona reticularis

Answer 42

- 17 Ketosteroids | - Sex hormones

Question 43

What pathologies increase adrenocortical hyperactivity

Answer 43

Due to hyperplasia, adenoma or cancer (rare) Cushing’s Syndrome ( excess cortisol) Conn’s Syndrome ( excess aldosterone) Adrenogenital syndrome ( excess androgens)

Question 44

what pathologies increases adrenocortical insufficiency

Answer 44

Addison’s disease

Question 45

What is adrenal cortex adenoma

Answer 45

Non-functional cortical adenoma Incidental finding on abdominal imaging Functional adenomas can cause Cushing’s Syndrome or Conn’s Syndrome

Question 46

Adrenal Medulla

Answer 46

Compact cells which secrete adrenaline and noradrenaline in response to intense emotional reaction (such as exams!) Flight or fight hormones Secretion results in vasoconstriction,  ↑heart rate,  blood sugar levels → Part of the organism’s defence to stress

Question 47

Phaechromocytoma

Answer 47

``` Tumour of the adrenal medulla 0.1-0.3% cause of treatable hypertension 10% Tumour 10% are familial as part of the MEN2 10% are extra-adrenal 10% bilateral 10% are malignant 10% arise in childhood ```

Question 48

what are the signs for Phaecromocytoma

Answer 48

Due to high levels of catecholamines Precipitous↑ BP + tachycardia, palpitations, headache, sweating, tremor & sense of apprehension Complications of ↑ BP CCF, IHD, cardiac arrhythmias, CVA

Question 49

what are the features of multi-nodular goitre

Answer 49

- compression of the trachea | - softening of the trachea leading to collapse- tracheomalacia