1: Principles of Endocrinology- Henry

Question 1

goal of the endocrine system

Answer 1

to coordinate and integrate cellular activity within the whole body by regulating cellular and organ function throughout life and maintaining homeostasis

Question 2

5 functions of endocrine system

Answer 2

1. regulate sodium and water balance
2. regulate calcium and phosphate balance
3. regulate energy balance
4. coordinate stress response
5. regulate reproduction, development, growth and senescence

Question 3

3 different types of hormones and their water solubility

Answer 3

peptides (more water soluble)
amino acids
steroids (less water soluble)

Question 4

endocrine v. paracrine v. autocrine v. intracrine

Answer 4

• into blood stream
• into interstitial space
• to the same cell
• within the same cell

Question 5

greater prtn binding = _______ half-life

Answer 5

increased

Question 6

briefly describe the formation and release of peptide hormones

Answer 6

• synthesized as pre-prohormones
• post-translational processing (cleavage, glycosylation)
• vesicle storage
• calcium dependent release

Question 7

how do peptide hormones travel in the blood?

Answer 7

hydrophilic, so they circulate freely

this gives a short half-life as well

Question 8

where are receptors for peptide hormones generally found?

Answer 8

cell surface - the hydrophilic peptide hormones can’t cross the cell membrane

Question 9

from what are all steroid hormones derived?

Answer 9

cholesterol

Question 10

how do steroid hormones travel in the blood?

Answer 10

lipophilic, so they circulate in a bound form

Question 11

where in general are steroid hormone receptors found?

Answer 11

intracellular receptors- steroid hormones are lipophilic and can cross plasma membranes

Question 12

name the catecholamines

Answer 12

NE
Epi
DA

Question 13

what are the catecholamines and thyroid hormones derived from?

Answer 13

tyrosine

Question 14

characteristics of catecholamines

Answer 14

hydrophilic, so they circulate freely and bind to cell surface receptors

Question 15

unique characteristics of thyroid hormone

Answer 15

hydrophilic but circulates bound and binds to intracellular receptors (needs transporter to get through membrane)

Question 16

what hormones use g-prtn receptors?

Answer 16

catecholamines and TSH, LH, and ADH

Question 17

what hormones use receptor protein tyrosine kinases?

Answer 17

insulin and growth hormone

Question 18

what hormones use intracellular receptors?

Answer 18

thyroid hormone and steroid hormones

Question 19

how is the thyroid hormone receptor different?

Answer 19

the receptor is already in the nucleus, repressing the gene transcription without thyroid hormone bound

usually receptor and hormone bind in the cytoplasm and then enter the nucleus to affect gene transcription

Question 20

the release of hormones is ______ and _______

Answer 20

pulsatile and periodic

monitor hormone excretion over 24 hrs, better than 1 time plasma reading

Question 21

what does tropic mean?

Answer 21

hormone that regulates the release of another hormone

Question 22

hypothalamus –> hypothalamus feedback loop

Answer 22

ultra-short loop

Question 23

anterior pituitary —> hypothalamus feedback loop

Answer 23

short loop

Question 24

target organ –> hypothalamus feedback loop

Answer 24

long loop

Question 25

what would the presence of a non-competitive inhibitor cause? competitive?

Answer 25

non-comp = decreased responsiveness

comp = decreased sensitivity

Question 26

shift to a right in the dose response curve…

Answer 26

decreased sensitivity

Question 27

decreased maximal response…

Answer 27

decreased responsiveness

Question 28

target hormone level low and pituitary hormone level high

Answer 28

failure of target organ

Question 29

target hormone level low and pituitary hormone level low

Answer 29

pituitary failure

Question 30

target hormone level high and pituitary hormone level high

Answer 30

autonomous secretion of pituitary hormone or resistance to target hormone action

Question 31

target hormone level high and pituitary hormone level low

Answer 31

autonomous secretion by target endocrine organ

Question 32

if you measure \_\_\_\_\_\_\_\_, 
a. glucose
b. calcium
c. estradiol
... you should also measure \_\_\_\_\_\_\_\_.

Answer 32

a. insulin
b. PTH
c. LH

Question 33

elevation of glucose and insulin indicates…

Answer 33

resistance

Question 34

oral glucose to test insulin release is an example of …

Answer 34

stimulation test

Question 35

dexamethasone to test negative feedback on ACTH release from pituitary is an example of….

Answer 35

suppression test