Endocrine pharmacology

Question 1

What are the releasing factors produced by the hypothalamus that act upon the anterior pituitary?

Answer 1

growth hormone releasing factor (GHF)
somatostatin (inhibits release of GH)
tryptophan releasing hormone (TRH)
Corticotrophin releasing factor (CRF)
Dopamine (inihbits prolactin release

Question 2

What cells in the anterior pituitary release prolactin?

Answer 2

Lactotrophs

Question 3

ACTH is released by what in the anterior pituitary

Answer 3

Corticotrophs

Question 4

What releases reproductive hormones?

Answer 4

the Gonadotrophs found in the anterior pituitary.

Question 5

What cells in the anterior pituitary release Growth hormone? and what condition occurs when growth hormone is not released?

Answer 5

Somatrophs. pituitary dwarfisim.

Question 6

trypotophan stimulating hormone released from where?

Answer 6

Thyrotrophs.

Question 7

What hormones are produced in the posterior pituitary and what are their functions?

Answer 7

Oxytocin. causes uterine smooth muscle contraction and breast myoepithelial contraction.

Vasopressin/ADH for water retention in the kidney.

Question 8

what is acromegaly? how to treat it?

Answer 8

when there is an excess of GH in adulthood.
causes growth of the soft tissues and mild hyperglycaemia.

Use somatostatin receptor agonists such as Octreotide. causes the anterior pituitary to stop releasing GH

Question 9

How do you treat pituitary dwafisim?

Answer 9

use somatropin HGH (human growth hormone) injections.
inject IGF-1.
Sermorlin can also be used as it is a GHRF analogue so can be used for diagnosis and to increase growth in children.

Question 10

What is the importance of thyroid hormones and what are some of their physiological effects?

Answer 10

key for metabolisim and developtment.

increase lipid, carbs and protein metabolisim.
oxygen consumption
heat production
basal metabolic rate

Question 11

What thyroid hormones are produced in the thyroid glands?

Answer 11

thyroxine (T4) and trilodothyronine (T3)

Question 12

what conditions can occur from a lack of iodine in the diet?

Answer 12

Non toxic goitre (Derbyshire neck)

If iodine deficency in childhood leads to Cretinisim.

Question 13

what is hypothyroidisim? what conditions does it cause?

Answer 13

Low levels of Thyroxine (T4) causes Myxodema which is the thickening of the skin and Hashimotos disease which is an auto immune disease. happens due to antibodies that cause a destruction of the thyroid tissue.

Question 14

What is hyperthyroidism and what conditions does it cause?

Answer 14

excess production of T4 and T3.
Graves disease. Auto immune where antibodies directly stimulate the thyroid gland to produce excess T4 and T3. leads to low levels of plasma TSH due to negative feedback inhibiton stopping its release from the Anterior pituitary.

Question 15

HOW CAN hyperthyroidism be treated?

Answer 15

surgical removal of part or all of thyroid gland and then provide life long hormonal replacement therapy.

use radioactive iodine to destroy part of gland

use drugs. such as thioureylenes like methimazole that inhibit iodination of tyrosine.

Question 16

What is protirelin?

Answer 16

a synthetic TRH that is used to diagnositcally test the functionality of the anterior pituitary to produce TSH.

Question 17

what enzyme do thioureylenes inhibit?

Answer 17

Thyroperoxidase.

Question 18

What is diabetes insipidus? how is it treated?

Answer 18

where there is damage to the pituitary that leads to a reduction or inability for it to secrete ADH. Leads to large volumes of dilute urine and extreme thirst.

can be managed with hormone replacements.

Question 19

What hormones are produced by the adrenal glands?

Answer 19

Androgens (sex hormones)

Aldosterone (body main mineralcorticoid for water and electrolyte regulation)

Cortisol

Question 20

How is aldosterone produced?

Answer 20

drop in extracellular fluid.
kidney activates release of renin
renin converts angiotensinogen to Angiotensin 1
AG1 gets converted to AG2 by ACE
AG2 acts on adrenal cortex to stimulate aldosterone production.

Question 21

Why can ACE inhibiton be used for treatment of Hypertension?

Answer 21

AG2 causes increase in BP and vasoconstiction so if ACE is inihbited then there is less AG2 produced that causes these hypertensive conditons.

Question 22

How does aldosterone effect sodium?

Answer 22

causes an increased retention of sodium which leads to increased extracellular fluid.

Question 23

What are the metabolic actions of cortisol?

Answer 23

Causes decreased protein syntheisis and increased protein degradation in skeletal muscles.

leads to decreased glucose uptake and increased lipid mobilisation in the adipose tissues.

causes liver to increase gluconeogenesis which leads to increased blood glucose and increased glycogen storage.

Question 24

How does cortisol decrease inflammation?

Answer 24

cortisol increases levels of lipocrotin that decreases the activity of phospholipase A2 that is an enzyme required for the production of Prostoglandins form arachidonic acids. leads to less PG induced inflammation.

Question 25

What step in aldeosterone and cortisol production does amminoglutethimide inhibit?

Answer 25

stops the conversion of cholesterol to pregnenolone. decreases the syntheisis of all steroid hormones by blocking the action of p450scc.