Endocrinology - Receptor Mechanisms

Question 1

Neurotransmitters

Answer 1

diffuses through the interstitial fluid between the adjacent nerve cells

Question 2

hormones

Answer 2

released into the blood. The blood carries them to target cells where they eleicit a physiologic response

Question 3

paracrines

Answer 3

chemical messangers released into the intersitial fluid where they exert effects on neighboring cells

Question 4

autocrines

Answer 4

chemical messengers released into the intersitial fluid act on the cell that secretes it

Question 5

pancreatic hormones regulates

Answer 5

digestion
utilization
storage of nutrients

Question 6

growth and thyroid hormones regulate

Answer 6

growth and development

Question 7

ADH and aldosterone regualte

Answer 7

ion and water metabolism

Question 8

estrogen, testosterone regulate

Answer 8

reproduction

Question 9

why do hormones only have effects on some cells

Answer 9

only target cells have receptors
hiher concentration in blood to some cells
conversion to a more active form in the target tissue

Question 10

permissive action of hormone

Answer 10

for hormone A to have its full effect, hormone B must be present, BUT hormone B does not have the effect itself

Question 11

amino acid derivative hormones

Answer 11

Ep, NE, Dopamine, thyroid hormone

Question 12

properties of amino acid derivative hormones

Answer 12

small
hydrophillic/lipophobic - act on cell membrane receptors - act through second messengers
stored in vesicles and released by exocytosis

Question 13

thyroid hormone properties

Answer 13

small
hydrophobic/lipophillic (can cross membrane)
escape from cells as they are made, stored bound to plasma proteins
slow, long-term effects

Question 14

Peptide and protein hormone properties

Answer 14

• fairly large
• string of amino acids
• short string (peptide) , long string (protein)
• hydrophillic / lipophobic
• rapid, short-term effects

Question 15

steroid hormone properties

Answer 15

• hydrophobic / lipophilic
• act on intracellular receptors - alter gene transcription
• escape from cells as they are made
• slow, long term effects

Question 16

peptide and protein hormones are formed as

Answer 16

larger precursor proteins that are cleaved to form the active hormone

Question 17

steroid hormones are derived from

Answer 17

cholesterol

Question 18

in steroid hormones, making proteins is __ but __

Answer 18

slow, long lasting

Question 19

in steroid hormones, acting through second messengers is __ but __

Answer 19

fast, short lasting effects

Question 20

steroid and thyroid hormone cant be

Answer 20

stored in cells because they cross membranes

Question 21

steroid and thyroidhormone are stored in

Answer 21

the blood, bound to proteins

Question 22

activation of second messenger systems

Answer 22

hormones that bind to cell membrane receptors

Question 23

why do hormones bind to cell membrane receptors

Answer 23

1. transfer information into the cell (lipophobic hormones can’t cross the cell membrane)
2. signal amplification (more produced each step)

Question 24

somatotropin

Answer 24

growth hormone

Question 25

what increases GH release

Answer 25

GnRH

Question 26

what decreases GH release

Answer 26

somatostatin

Question 27

what decreases GH release

Answer 27

somatostatin

Question 28

GNRH activates

Answer 28

GS (stimulates Adenylate cyclase)

Question 29

somatostatin activates

Answer 29

GI (inhibit adenylate cyclase)

Question 30

increase in cAMP increases

Answer 30

GH release