Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

FHB > Endocrinology 2- Hormone Bioavailability > Flashcards

Endocrinology 2- Hormone Bioavailability Flashcards

1
Q

How can hormone transport affect bioavailability

A

How much is bound vs unbound (binding proteins), kinetics (half life and metabolism)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

How can target tissues affect hormone bioavailability

A

Receptors (if there are any mutations, desensitization, half life issues, up or down regulation of the receptors); as well as chaperone and heat shock proteins that may be associated with the receptor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

How can hormone synthesis and release affect hormone bioavailability

A

Enzymatic activity; processing and packaging

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How regulatory mechanisms can affect hormone bioavailability

A

Feedback mechanisms, circadian rhythms, aging, pulsitility

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is some information the classification of a hormone’s chemical makeup can tell you?

A

How the hormone is synthesized and released from the cell, how long a hormone is in circulation, how it travels in circulation (bound/unbound), the receptor type that will mediate the action, cellular signaling pathways

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Usual half life of an amine hormone

A

2-3 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Two types of amine hormones (chemically speaking)

A

Catecholamines, indoleamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are Catecholamines (chemically speaking, what are they derived from)

A

Tyrosine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are indoleamines derived from chemically speaking

A

Tryptophan

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the general half life of a peptide or protein hormone

A

Can vary - on avg 4-170 minutes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

General half life of a steroid hormone

A

Minutes to several hours

Very helpful, thank you

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Tyrosine derived Catecholamines hormones include what 3 main players

A

Dopamine, epinephrine, norepinephrine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the rate limiting step in Catecholamine biogenesis

A

Tyrosine hydroxylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What 2 main body organs houses dopamine

A

Brain (substantia migraine, VTA, accurate nucleus), and adrenal gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

In brain, what is the “endocrine” generator of dopamine

A

Arcuate nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the enzyme that catalyzes the reaction to generate norepinephrine

A

Dopamine b-hydroxylase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Where is most norepinephrine generated

A

Neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the nerve from SNS that innervates adrenal medulla to get NE/E?

A

Splanchnic nerve

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are the cells in the adrenal medulla that make Epinephrine

A

Chromaffin cells (in adrenal medulla)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are the major 2 indoleamines in the body

A

Serotonin and melatonin

21
Q

What is the rate limiting enzyme in indoleamine synthesis

A

Tryptophan hydroxylase

22
Q

What is the first step in indoleamine synthesis

A

AADC (aromatic L amino acid decarboxylase)

23
Q

Where is the majority of serotonin produced

A

Gut (enterochromaffin cells)

24
Q

What converts serotonin to melatonin (rate limiting step)

A

N-acetyltransferase

25
Q

What is special about n-acetyltransferase

A

It is only active at night

26
Q

How do we break down amine hormones? Two pathways

A

MAO (monoamine oxidase) and COMT (Catecholamines-o-methyltransferase)

27
Q

MAO

A

Monoamine oxidase - removes an amine group, oxidative delaminating - get aldehyde instead of amine. Inactivates both Catecholamines and indoleamines

28
Q

MAOI

A

MAOI’s are pharmaceutical drugs used to treat depression and anxiety disorders

29
Q

COMT

A

Adds methyl group to allow substance to be metabolized, specific to catecholamine. This is inhibited by entacapone which is a Parkinson’s drug, to try to increase levels of dopamine.

30
Q

Monoamine deaminating steps

A

1 - deamination, form aldehydes
2- aldehydes are converted to alcohol or metabolizes by aldehyde dehydrogenase or aldose reductase
3. DHPG is the primary metabolite in sympathetic nerves - major pathway for catecholamine metabolism

31
Q

COMT methylation - steps

A

Major source of metanephrine and normetanephrine in adrenal gland - converts DHPG to MHPG which is a precursor of VMA — this is excreted into urine — if you have high Catecholamines especially. This is a good diagnostic tool to look for tumors

32
Q

How are protein/peptide hormones first generated?

A

Preprohormone

33
Q

What does a preprohormone consist of?

A

Signal peptide + hormone + additional copeptides

34
Q

Where is the signal peptide cleaved

A

In the ER

35
Q

Where are copeptides cleaved from prohormone

A

This is going to be cleaved in Golgi/sometimes within vesicles themselves

36
Q

Where are steroid hormones made

A

Placenta, adrenal gland, testes, ovaries

37
Q

21 carbon steroids include what 3 hormones

A

Glucocorticoids, mineralocorticoids, and progestins

38
Q

19-carbon steroids include what hormones

A

Androgens

39
Q

18-carbon steroid hormones includes

A

Estrogens

40
Q

What is our body’s main secosteroid

A

Vitamin d

For dick

41
Q

Precursor to all of our steroid hormones

A

Pregnenolone

42
Q

What are the few instances we will see positive feedback

A

Parturition (childbirth) and lactation (suckling) — both of these include oxytocin
Ovulation — LH stimulates estradiol in developing follicle, estradiol stimulates more LH, then release of OOcyte eventually stops loop

43
Q

What is an endocrine axis?

A

A three tiered biological system made of hypothalamic neurons, anterior pituitary cells, and peripheral endocrine gland

44
Q

What is a long feedback loop

A

Feedback of the molecule feeding back at pituitary or hypothalamic level

45
Q

What is a short feedback loop

A

Molecule from pituitary goes back and feeds to hypothalamus to tell it to fucking stop

46
Q

2 major types of negative feedback

A

Physiological response drive

Endocrine axis driven

47
Q

Physiological response driven negative feedback

A

Endocrine gland releases hormone, hormone does its thing to target organ, physiology is changed, for example blood glucose, gland detects change in physiology and stops releasing as much hormone

48
Q

Endocrine axis driven negative feedback

A

Peripheral organ releases a hormone and directly says “stop” to pituitary or hypothalamus, or pituitary feeds back to hypothalamus (long/short loops respectively) and this is what stops the cycle

49
Q

What are some factors that affect circulating hormone levels

A

Age, body weight, time of day, male/female, diet

FHB (54 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions