Endocrine Control of Growth (Nutting)

Question 1

What is catch up growth?

Answer 1

(growth is stunted by illness) → catch up growth is the growth “spurt” that occurs to bring height or weight back up to ~nml

Question 2

What is compensatory growth?

Answer 2

when parts of an organ is removed, the remaining organ hypertrophies to compensate
(i.e. kidney, liver, adrenals)

Question 3

What are the requirements for growth

Answer 3

1. proper nutrition
2. sufficient hormones at the right time
3. good psychosocial environment

Question 4

What hormones play a role in normal somatic growth?

Answer 4

GH, IGF-1
Vit D
Sex hormones
insulin 
TH
GI hormones (for nutrition digestion and abs)

Question 5

What hormones are needed for juvenile stage of growth? Adolescent?

Answer 5

juvenile: GH + T3 + Vit D + insulin
adeoles: GH + T3 + Vit D + insulin + sec hormones

Question 6

Is psychosocial dwarfism reversible

Answer 6

yes, they must be removed from envrio

Question 7

how does excess and deficient growth hormone effect linear growth, skeletal maturation, and adult stature (if untreated)

Answer 7

Excess:
liner growth: ↑
skeletal maturation: nml
adult stature: ↑ = giantism

Deficient:
liner growth: ↓
skeletal maturation: delayed
adult stature: ↓ = hyposomatotrophic dwarfism

Question 8

how does excess and deficient thyroid hormone effect linear growth, skeletal maturation, and adult stature (if untreated)

Answer 8

Excess:
liner growth: slight ↑
skeletal maturation: slight advanced
adult stature: minimal

Deficient:
liner growth: ↓
skeletal maturation: delayed
adult stature ↓

Question 9

how does excess cortisol effect linear growth, skeletal maturation, and adult stature (if untreated)

Answer 9

Excess:
liner growth: ↓
skeletal maturation delayed
adult stature: ↓

Question 10

how does excess and deficient androgen effect linear growth, skeletal maturation, and adult stature (if untreated)

Answer 10

Excess:
liner growth: ↑ then ↓
skeletal maturation: advanced
adult stature: ↓

Deficient:
liner growth: ↑ in extremities
skeletal maturation: delayed (adolescent)
adult stature: eunuchoidal (tall, long arms and legs)

Question 11

how does deficient estrogen effect linear growth, skeletal maturation, and adult stature (if untreated)

Answer 11

Deficient:
liner growth: ↑ extremities
skeletal maturation: delayed (adolescent)
adult stature: ↑

Question 12

somatamedin is aka

Answer 12

IGF-1

Question 13

somatocrinin is aka

Answer 13

GHRH

Question 14

eunuchoidal adult stature

Answer 14

untreated androgen deficiency

Question 15

somatotrophin is aka

Answer 15

GH

Question 16

structure of GH

Answer 16

22K from (90%) and 20K form (10%)

Question 17

isolated GH deficiency leads to what condition/dz

Answer 17

hyposomatotrophic dwarfism

Question 18

Why are cows given GH?

Answer 18

increases milk production

Question 19

What hormones promote tallness?

Answer 19

GH + T3, which is permissive

Question 20

What inhibits tallness?

Answer 20

gonadal steroids

Question 21

effect of GH on bone

Answer 21

↑long bone growth at epiphyseal growth plate

↑ bone thickening (acromegaly)

Question 22

tibia test

Answer 22

the more growth hormone there is the wider the tibial plate is (less GH = narrower plate)

Question 23

IGF-1 deficiency leads to what condition/dz

Answer 23

laron dwarfism

pygmies

Question 24

effect of GH on DNA

Answer 24

↑ synthesis ∴ ↑ cel l #?

Question 25

effect of GH on RNA

Answer 25

↑ t ,m, and rRNA to increase protein synthesis

Question 26

how does GH affect fat metabolism

Answer 26

delayed effect to ↑ lipolysis ∴ ↑ FFA

Question 27

effect of GH on carbohydrate metabolims

Answer 27

MILDLY impairs glc uptake and utilization, GH must be ↑↑↑ for a long time to cause insulin resistance/T2DM

Question 28

what is the somatomedin hypothesis vs the dual effector hypothesis

Answer 28

both explain hoe GH increases growth somatomedin hypot: GH acts on the liver to ↑ IGF-1 secretion which directly acts on long bones/other target to ↑ growth (i.e. says GH has indirect action) dual effector hypoth: GH acts on the liver to ↑ IGF-1 secretion which directly acts on long bones/other target to ↑ growth but GH also acts directly on bones, muscle, adipose, etc to ↑ growth

Question 29

What is the secretion pattern of GH and when is it secreted?

Answer 29

episodic (ultradian) | major secretion at night (w/ deep sleep)

Question 30

How do you treat kids with GH insensitivity due to GH receptor mutation

Answer 30

give them IGF-1

Question 31

What is the major side effect of IGF-1 therapy

Answer 31

hypoglycemia (IGF = INSULIN LIKE growth factor)

Question 32

How do serum IGF-1 levels compare in acrogmegaly, hypopituitarism, and normal pts?

Answer 32

acro: HIGH, 4-10 U/mL nml: present, 1-2 U/mL hypopit: almost absent, <.1

Question 33

``` What effect does GH have on ... and what does this change correlate to? nitrogen sodium potassium phosphorus ```

Answer 33

nitrogen ↑ = ↑pro synthesis sodium ↑ = ↑extracellular space potassium ↑ = ↑ intracellular space phosphorus ↑ = ↑ bone growth

Question 34

What effect does GH have on T3 actions?

Answer 34

↑ sensitivity GHRH ↑ synthesis somatotrophs ↑ responsiveness of target cells

Question 35

What effect does low dose cortisone have on GH? larger dose?

Answer 35

small = no effect, GH still growth promoting high = ↓GH effectiveness

Question 36

Is insulin required for growth?

Answer 36

yes | *in rats, no insulin = no growth

Question 37

somatostatin inc or dec GH

Answer 37

dec

Question 38

IGF-1 inc or dec GH

Answer 38

dec (negative feedback)

Question 39

exercise inc or dec GH

Answer 39

inc

Question 40

postprandial hyperglycemia inc or dec GH

Answer 40

dec

Question 41

TH inc or dec GH

Answer 41

inc

Question 42

estrogens inc or dec GH

Answer 42

inc

Question 43

hyoiglycemia inc or dec GH

Answer 43

inc

Question 44

glucocorticoids inc or dec GH

Answer 44

dec

Question 45

hyperthyroidism inc or dec GH

Answer 45

dec

Question 46

hypothyroidism inc or dec GH

Answer 46

dec

Question 47

progesterone inc or dec GH

Answer 47

dec

Question 48

GH conc inc or dec with age

Answer 48

inc unitl we are ~24 and then falls

Question 49

testosterone inc or dec GH

Answer 49

inc

Question 50

insulin inc or dec GH

Answer 50

inc

Question 51

What hormones are responsible for the pubertal growth spurt?

Answer 51

GH and IGF-1

Question 52

how is GH affected in psychosocial deprivation? how is it measured?

Answer 52

decreased; measure IGF-1