Endocrinology

Question 1

Catecholamines general mechanism of action. Speed & duration of action

Answer 1

Bind to G protein-coupled receptors. Extremely fast & short-lived

Question 2

Tyroxine & triiodothyronine general mechanism of action. Speed & duration of action

Answer 2

Bind intracellularly. Slow onset, longer duration.

Question 3

Tropic hormones originate from…

Answer 3

Brain & anterior pituitary gland

Question 4

Suprachiasmatic nucleus

Answer 4

receives signal from retinae

Question 5

Hypothalamus hormones

Answer 5

GnRH, GHRH, TRH, CRF(corticotropin releasing factor), PIF (prolactin-inhibiting factor)

Question 6

ACTH

Answer 6

Adrenocorticotropic hormone in anterior pituitary, stimulate cortisol release from adrenal cortex

Question 7

Anterior pituitary hormones (which are tropic and which are direct)

Answer 7

FLAT (tropic) PEG (direct)

FSH, LH, ACTH, TSH, Prolactin, Endorphins, GH

Question 8

Posterior pituitary hormones

Answer 8

Oxytocin and ADH

Question 9

Acromegaly

Answer 9

too much GH as adult

Question 10

How nipple stimulation cause activation of hypothalamus

Answer 10

1. Oxytocin release from posterior pituitary

2. Hypothalamus stop releasing dopamine into anterior pituitary

Question 11

Functions of thyroid gland

Answer 11

1. Set basal metabolic rate through T3 and T4

2. Set basal calcium levels through calcitonin

Question 12

T3 and T4 (triiodothyronine and thyroxine)

Answer 12

1. Make energy production more/less efficient

2. Alter utilization of glucose and fatty acids (increased T3 & T4 = increased respiration)

Question 13

Cretinism

Answer 13

mental retardation and developmental delay due to low [T3] or [T4]

Question 14

PTH roles

Answer 14

Antagonistic to calcitonin. Activates vitamin D, which is required for Ca and K reabsorption from the gut.

Question 15

Calcium functions

Answer 15

1. Bone structure & strength
2. Release of neurotransmitters from neurons
3. Regulation of muscle contraction
4. Cofactor for blood clots

Question 16

Adrenal cortex types of hormones secreted

Answer 16

1. Glucocorticoids: cortisol & cortisone that increase blood glucose levels and decrease protein synthesis. Decrease inflammation and immunogenic response.
2. Mineralcorticoids: aldosterone big
3. Cortical sex hormones:

Question 17

Renin-angiotensin-aldosterone system

Answer 17

JG cells in kidney secrete renin, which cleaves angiotensinogen to angiotensin I, which is converted primarily in lung to angiotensin II. Angiotensin II stimulates adrenal cortex to secrete aldosterone.

Question 18

Adrenal Medulla hormones

Answer 18

Epinephrine and NE.

Question 19

Pancreas Islets of Langerhans Hormones

Answer 19

1. Alpha: glucagon
2. Beta: insulin
3. Delta: Somatostatin

Question 20

Glucagon functions

Answer 20

1. Stimulate degradation of protein & fat
2. Convert glycogen to glucose
3. Production of new glucose via gluconeogenesis

Question 21

Somatotstatin functions

Answer 21

1. Inhibitor of both insulin and glucagon secretion
2. Stimulated by high blood glucose & amino acid concentration
3. Decreases GH secretion

Question 22

Pineal gland hormones secreted

Answer 22

Melatonin

Question 23

Erythropoietin: what organ it’s secreted in by what, what it stimulates

Answer 23

Hormone secreted by kidneys in response to low oxygen in blood, stimulate bone marrow to increase erythrocyte production.

Question 24

Atrial natriuretic peptide (ANP): what organ it’s secreted in by what, what it stimulates

Answer 24

Hormone secreted by heart in response to high blood volume. Antagonistic to aldosterone: reduces water, sodium, and adipose load, reducing blood pressure.

Question 25

Thymosin: what organ it’s secreted, what it stimulates

Answer 25

Secreted by thymus, important for T-cell development & differentiation