Pharm: Hormones, Receptors and Signalling

Question 1

does the endocrine system tend to have ducted or ductless glands?

Answer 1

ductless

Question 2

how do endocrine glands communicate with other organs?

Answer 2

via hormones

Question 3

how is hormone signalling made specific?

Answer 3

chemically distinct hormone
specific receptor for each hormone
distinct distrubution of receptors

Question 4

is there a specific hormone for each receptor or multiple?

Answer 4

one hormone per receptor

Question 5

what are the categories of hormone found in the body?

Answer 5

modified amino acids
steroids
peptides
proteins

Question 6

is adrenaline a steroid?

Answer 6

no, its a modified amino acid

Question 7

what kind of hormone are thyroid hormones?

Answer 7

modified amino acids

Question 8

what kind of hormone is ADH?

Answer 8

peptide

Question 9

what kind of hormone is insulin?

Answer 9

protein

Question 10

what kind of hormone are sex hormones?

Answer 10

steroid

Question 11

what are the 3 types of gland?

Answer 11

autocrine
paracrine
endocrine

Question 12

which gland can signal the furthest?

Answer 12

endocrine

Question 13

how far can hormones travel from a paracrine gland and via what?

Answer 13

to nearby cells via extracellular fluid

Question 14

how far can hormones travel from an endocrine gland and why?

Answer 14

travels in the blood so can go to virtually any cell

Question 15

how far can hormones travel from an autocrine gland?

Answer 15

can only respond to itself

Question 16

what happens once a hormone binds to its receptor?

Answer 16

initiates signal transduction

Question 17

what stops the signal transduction of a hormone?

Answer 17

enzyme mediated inactivation in liver or site of action

Question 18

what is the main job of signal transduction of a hormone?

Answer 18

amplifies the original signal

Question 19

name the 2 main types of actions made by hormones

Answer 19

complementary

antagonistic

Question 20

how does complementary hormonal action work?

Answer 20

lots of different hormones regulate complex physiological functions on both short and long time scales

Question 21

would the role of insulin, GH, IGF-1 and sex steroids in growth be a complementary or antagonistic action?

Answer 21

complementary

Question 22

how does an antagonistic hormonal action work?

Answer 22

via balance of opposing influences eg insulin and glucagon

Question 23

where are amines stored?

Answer 23

vesicles

Question 24

how are amines released?

Answer 24

by calcium dependent exocytosis

Question 25

are amines hydrophilic or hydrophobic? what does this mean for its transport?

Answer 25

hydrophilic so travel quite freely in plasma

Question 26

name the categories of hormone that are presynthesised rather than made on demand?

Answer 26

amines peptides proteins

Question 27

how are peptides and proteins released?

Answer 27

calcium dependent exocytosis

Question 28

are peptides and proteins hydrophilic or hydrophobic?

Answer 28

hydrophilic

Question 29

are steroids hydrophobic or hydrophilic?

Answer 29

hydrophobic

Question 30

how are steroids transported in the blood?

Answer 30

bound to plasma proteins

Question 31

what kind of hormone is cholesterol?

Answer 31

steroid

Question 32

what effect do stimuli have on steroids?

Answer 32

increased cellular uptake and availability of cholesterol

Question 33

what does cholesterol get converted to when stimulated?

Answer 33

pregnenolone

Question 34

what hormones other than steroids are insoluble in plasma?

Answer 34

thyroid hormones

Question 35

how do carrier proteins increase their half lives?

Answer 35

when circulating in a carrier protein

Question 36

if a substance has "binding-globulin" after it, what is it?

Answer 36

a carrier protein

Question 37

what substances are binded by the carrier protein sex steroid binding globulin?

Answer 37

testosterone | oestradiol

Question 38

what substances does the albumin carrier protein transport?

Answer 38

steroids | thyroxine

Question 39

what substances do not require a carrier protein?

Answer 39

hydrophilic substances that are soluble in plasma

Question 40

main role of carrier proteins?

Answer 40

maintain constant concentrations of free lipophilic hormone in the blood

Question 41

does a hormone have to be free to cross the capillary wall when heading to a cell to bind to its receptor?

Answer 41

yes

Question 42

how are surges in hormone secretion combatted?

Answer 42

by binding the hormone to a carrier protein

Question 43

what can happen when there is not enough free hormone in the plasma?

Answer 43

bound hormone dissociates from carrier protein

Question 44

what is the primary determinant of plasma concentration?

Answer 44

rate of secretion

Question 45

what mechanism maintains plasma concentration at a set level?

Answer 45

negative feedback

Question 46

most important 2 routes of elimination?

Answer 46

metabolism by liver | excretion by kidney

Question 47

how do you work out plasma concentration of hormone?

Answer 47

rate of secreton - rate of elimination

Question 48

which hormone has the shortest half life?

Answer 48

amines

Question 49

which hormone has the longest half life?

Answer 49

steroids | thyroid hormones

Question 50

name the 3 main types of hormone receptor?

Answer 50

GPCR receptor kinase nuclear receptor

Question 51

what hormones activate GPCRs?

Answer 51

amines | proteins/peptides

Question 52

what hormones activate receptor kinases?

Answer 52

proteins/peptides

Question 53

what receptors are on the cell surface?

Answer 53

GPCR | receptor kinase

Question 54

what does an intracellular receptor mean?

Answer 54

its ligand is lipophilic so it allows diffusion across the membrane

Question 55

what effect does insulin have on receptor kinases?

Answer 55

autophosphorylates intracellular tyrosine and recruits other proteins = cellular effects

Question 56

what do transactivation and transrepression mean?

Answer 56

``` TA = switched on TD= switched off ```