Lecture 1: intro to endocrine

Question 1

hypothalamus secretes what hormones?

Answer 1

TRH CRH GnRH Somatostatin Dopamine

Question 2

ant. pituitary secretes what hormones?

Answer 2

TSH FSH LH ACTH MSH Growth hormone Prolactin

Question 3

post pituitary secretes what hormones?

Answer 3

ADH Oxytocin

Question 4

thyroid secretes what hormones?

Answer 4

T3,T4 Calcitonin

Question 5

parathyroid secretes what hormones?

Answer 5

PTH

Question 6

pancreas secretes what hormones?

Answer 6

Insulin Glucagon

Question 7

adrenal medulla secretes what hormones?

Answer 7

NE

EPI

Question 8

kidney secretes what hormones?

Answer 8

Renin

1,25-Dihydroxycholecalciferol

Question 9

adrenal cortex secretes what hormones?

Answer 9

Cortisol
Adrenal androgens
aldosterone

Question 10

testes secrete what hormones?

Answer 10

testosterone

Question 11

ovaries secrete what hormones

Answer 11

estradiol

progesterone

Question 12

corpus luteum secretes what hormones?

Answer 12

estradiol

progesterone

Question 13

placenta secretes what hormones

Answer 13

hCG
Estriol
Progesterone
hPL

Question 14

what the the three general classes of hormones?

Answer 14

1) proteins and peptides
2) amines (derived from tyrosine)
3) steroids (from cholesterol)

Question 15

what are examples of steroid hormones?

Answer 15

Cortisol, aldosterone, estradiol & estriol, progesterone,
testosterone, & 1,25-
dihydroxycholecalciferol

Question 16

where does cholesterol come from for synthesis of steroids?

Answer 16

– Approximately 80% is taken up as LDL particles through
receptor-mediated endocytosis
– De novo synthesis from acetyl coenzyme A (acetyl CoA)

Question 17

what are the two mechanisms of interactions of steroid hormones

Answer 17

– Genomic (common theory): modulate gene transcription by
interaction with intracellular, nuclear receptors
– Nongenomic: rapid steroid actions

• Specific-receptor-mediated actions or direct steroid-
membrane interactions

Question 18

what are the two groups of amine hormones derived from tyrosine?

Answer 18

1) catecholamines (Dopamine, Epi, NE)

2) thyroid hormones

Question 19

what are two ways hormones are turned on or off?

Answer 19

1) neural mechanism

2) feedback mechanism

Question 20

what uses + feedback mech?

Answer 20

1) menstrual cycle and estrogen

2) delivery of fetus and oxytocin

Question 21

Long-loop feedback:

Answer 21

hormone released from
the 3rd tier (peripheral
endocrine gland) feeds
back all the way back to
the 1st tier
(hypothalamus) & 2nd
tier (pituitary)

Question 22

Short-loop feedback:

Answer 22

hormone secreted from
the 2nd tier feeds back
to the 1st tier

Question 23

Ultra short-loop

feedback:

Answer 23

Gland inhibits

its own secretion

Question 24

Suprachiasmatic nucleus (SCN)

Answer 24

-in hypothalamus
• Impose a circadian rhythm on the secretion of
hypothalamic releasing hormones & endocrine
axes

Question 25

Pineal gland

Answer 25

-in hypothalamus
• Releases melatonin which feedback to the SCN
information about day-night

Question 26

how is the sensitivity of a receptor measured?

Answer 26

hormone concentration that

produces 50% of the maximal response (EC50)

Question 27

what are two ways hormone responsiveness can change?

Answer 27

– Changing the # of receptors
– Changing the affinity of the receptors for the
hormone

Question 28

hormones that use adenylyl cyclase mechanism

Answer 28

ACTH
LH
FSH
TSH
ADH
HCG
MSH
CRH
calcitonin
PTH
glucagon
B1 and B2 receptors 
GHRH

Question 29

hormones that use phospholipase C mech

Answer 29

GNRH
TRH
angiotensin II
ADH
oxytocin 
alpha 1 receptors

Question 30

hormones that use steroid hormone mech

Answer 30

glucocorticoids
estrogen
progesterone
testosterone
aldosterone
1,25- dihydroxycholecalfierol 
thyroid hormone

Question 31

hormones that use RTK mech

Answer 31

insulin
IGF-1
GH
Prolactin

Question 32

hormones that use cGMP mech

Answer 32

-ANP

NO