Endocrine - Intro Flashcards

1
Q

Define

Hormones

A

Chemical signals (ligands) used for cell-to-cell communication by binding to receptors on/in target cells

Secretion of hormones is regulated

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

Classic Endocrine Glands

List the 7 main glands

A
  1. Hypothalamus
  2. Pituitary Gland (Anterior/Posterior)
  3. Thyriod Gland
  4. Parathyroid Gland
  5. Adrenal Glands
  6. Pancreas
  7. Gonads (Ovaries and Testes)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What effect does dysregulation of hormones have on the body? What causes it?

A

Disease can occur
caused by hypo/hypersecretion and/or nonfunctional receptors

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

What are some examples of diseases caused by dysregulation of hormones?

Know Some

A

Type I/II Diabetes
Hypo/Hypersecretion
PCOS
Addison’s Disease
Osteoporosis
Infertitility
Growth Defects

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

Which of the following is NOT an endocrine gland?
A. Ovary
B. Pancreas
C. Lung
D. Thyroid
E. Hypothalamus

A

C. Lung

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

How do cells communicate with each other?

General pathway of cell communication

A

Signal - Receptor - Response

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

What are the types of cellular communication?

A

Autocrine/Paracrine
Endocrine (Hormonal)
Neural
Neuroendocrine

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

What are typical responses seen in cell to cell communication?

A

Opening and closing of ion channels
Phosphorylation of intracellular proteins
Changing cytoskeletal structure
Making new proteins

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

Define

Autocrine Signaling

A

Signal is released by one cell and that signal binds to a receptor on the SAME cell to elicit a response

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

Define

Paracrine Signaling

A

Signal is released by one cell and that signal bnds to a receptor on a different cell in the local area to elicit a response

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

Define

Endocrine/Hormonal Signaling

A

Signal is released by one cell and the signal travels through the blood to reach its target cell

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

Define

Neural Signaling

A

Communication between nerve cells where messages between cells are sent using action potentials and neurotransmitters

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

Define

Neuroendocrine Signaling

A

A nervous cell releases a hormone into the bloodstream where it travels to reach the target cell

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

A cell produces and releases a molecule into the extracellular matrix. This molecule then binds to receptors on the same cell. This most accurately represents which type of cellular signaling?

A

Autocrine signaling

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

What is the pathway of thyroid hormone?

A
  1. Hypothalamus secretes TRH into bloodstream
  2. TRH travels to anterior pituitary gland to stimulate release of TSH into bloodstream
  3. TSH travels through the blood to reach the thyroid gland
  4. TSH stimulates synthesis and release of T3 and T4 in/from thyroid gland
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are the major classes of hormones?

A

Peptide/protein
Catecholamines
Steroid
Iodothyronies or thyroid hormones

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

Hormone behavior depends on…

A

Chemical composition

Form fits function

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

Structure of:

Peptide/protein hormones

A

Unique amino acid sequences

Insulin, GH, ADH

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

Structure of:

Catecholamines

A

Hormones modified from Tyrosine
Amino Acid Derived

Epi, NE, DA

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

Structure of:

Steroid

A

Hormones modified from Cholesterol

Estrogen, Testosterone, Cortisol, Vitamin D

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Structure of:

Iodothyronies or thyroid hormones

A

Hormones derived from tyrosine and iodine
amino acid derived

T3 and T4

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Epinephrine is classified as which type of hormone?

A

Catecholamine Hormone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Define:

Hydrophilic

A

Soluble in water but not oil
Water loving
Polar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Define:

Hydrophobic

A

Soluble in oil but not water
Water Hating
Nonpolar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Define

Lipophilic

A

Nonpolar
Water hating
Hydrophobic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Define

Lipophobic

A

Polar
Water Loving
Hydrophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Chemical Characteristic

A steroid hormone is…

Hydrophilic, Hydrophobic, Polar, Nonpolar, Lipophilic, Lipophobic

A

Hydrophobic
Non Polar
Lipophilic

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Blood is an aqueous solution. How can hydrophobic (nonpolar) steroid hormones travel through the blood?

Aqueous = plasma and cells in blood

A

Bound to binding proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Binding proteins that have high affinity and low capacity for hormones…

What does it mean for the transport of hormones?

A

Have strong binding but cannot move many hormone molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Binding proteins that have low affinity but high capacity for a hormone…

What does it mean for the transport of hormones?

A

Can carry alot of hormone molecules but have weak binding

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

How do SHBG, TBG, and CBG bind steroids?

Sex-hormone binding globulin, Thyroid BG, Cortisol BG

A

With high specificty but low capacity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

How does albumin bind steroids?

A

It has high affinity to bind to any steroid nonspecifically but with low affinity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What is the purpose of binding proteins?

A

They increase the half - life of hormones so they are not metabolized by liver and kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What is required before a hydrophobic hormone can be eliminated?

A

Metabolism by the liver and kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Free hormones are…

Not bound

A

Active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

Bound hormones are…

A

Inactive

Can’t enter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Circulating hormone concentrations depend on….

What is the equation?

A

Binding proteins
Total [hormone] = [free hormone] + [bound hormone]

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Bound hormones represent…

What is their purpose?

A

A back-up supply of hormones that can be used when hormone secretion is low

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

If binding protein concentration in the blood increases, what happens to total hormone concentration?

and [free hormone]?

A

[Total hormone] increases
[Free Hormone] doesn’t change

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What is the relationship between [total hormone] and binding proteins?

A

decrease [total hormone] increase release of hormones from binding proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

How are Peptide/Protein Hormones (Polar) produced, processed, and released?

A
  1. DNA
  2. Transcription of DNA to mRNA in nucleus
  3. mRNA moves to ER by ribosomes for translation into Preprohormone (NH2-signal hormone-copeptides)
  4. Unnecessary signals are cleaved in ER to become prohormones
  5. Prohormones move to golgi for processing and packaging into hormones
  6. hormones and copeptids are released in granules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

Where are peptide/protein hormones stored?

A

In granules/vesicles until they are signaled to be released

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

How are catecholamines synthesized?

A
  1. Tryosine converted to DOPA by enzyme 1
  2. DOPA converted to Dopamine by enzyme 2
  3. Dopamine converted to NE by enzyme 3
  4. NE converted to Epi by PNMT

Start with amino acid - then use enzymes to convert to different catecholamines

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Where are catecholamines made and stored?

When are they released?

A

Made and stored in cytosol

Released when signaled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

How do polar hormones cross the hydrophobic cell membrane?

A

They NEED to bind to a receptor embedded in the cell membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Define

Ionotropic

A

Hormone binding directly opens ion channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

Define

Metabotropic

A

Hormone binding stimulates secondary messenger cascades

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

When protein hormones bind to receptors, cellular responses occur…

What is their speed?

A

Fast
milliseconds-minutes

49
Q

Which of the following statements is most accurate concerning polar hormones?
A. Increased numbers of mitochondria will be observed in cells secreting protein hormones
B. Prohormones are modified within the ER
C. Insulin must bind to a receptor embedded in the cell membrane
D. Threonine is enzymatically converted to NE and Epi
E. When protein hormones bind to receptors, cellular responses occur in hours/days.

A

C. Insulin must bind to a receptor embedded in the cell membrane

50
Q

What is the common precursor of steroids?

A

Cholesterol

51
Q

Steroids are released….

A

Immediately

Not stored in cells

52
Q

What structures are involved in steroid hormone biosynthesis in steroid hormone producing cells?

A

Mitochondria
Smooth ER
Lipid Droplets

53
Q

What determines which hormons are produced by cells?

A

Specific enzymes

54
Q

Where are thyroid hormones made?

A

In a thyroid follicle

55
Q

What makes up a thyroid follicle?

A

Follicular cells + colloid

56
Q

T3 and T4 are made from…

A

Iodine and Thyroglobulin (Tg)

Tg is a protein produced in follicular cells

57
Q

Coupling of Tg and Iodine occurs in….

A

The colloid

58
Q

What happens to colloid after production of thyroid hormones?

A

Colloid is endocytosed back into the follicular cells

59
Q

What is the polar behavior of Thyroid Hormones?

A

T3 and T4 are stored in cytoplasmic vesicles until stimulated by TSH

60
Q

What is the non-polar behavior of T3 and T4?

A

T3 and T4 travel through the circulation bound to albumin and TBG

61
Q

Most steroid hormones are made in the…

A

Adrenal Cortex or Gonads

62
Q

Why are steroid hormones not stored in endocrine cells?

A

Because of their lipophilic nature
They are made on demand and diffuse out of the endocrine cell

63
Q

Steroid and Thyroid Hormone Signaling

Hydrophobic molecules CAN…, so they bind to…

A

Hydropobic molecules can pass through the cell membrane so they bind to intracellular receptors in the cytoplasm or nucleus

64
Q

Steroid and Thyroid Hormone Signaling

What occurs once steroid/thyroid hormones bind intracellular receptors?

A

Receptors typically dimerize, and then bind to DNA
Genes are up or down regulated (hormone receptor complexes promote or prevent gene transcription and protein translation)

65
Q

Responses to steriod and thyroid signaling are…

What is their speed?

A

Slow
Hours - Days

66
Q

NE causes vasoconstriction of vascular smooth muscle in skin, but vasodilation of vascular smooth muscle that perfuses skeletal muscle. How is this possible?

A

It binds different receptors that couple different transduction pathways and yield different results.
NE binds a1 receptors in vascular smooth muscle in the skin
NE binds b2 receptors in skeletal muscle

67
Q

Which hormone(s) are made in advance and stored in secretory vesicles?

A

Peptide Hormones
Catecholamines

68
Q

Which hormone(s) are synthesized on demand from precursors?

A

Steroid Hormones

69
Q

Which hormone(s) are made in advance with their precursor stored in secretory vesicles?

A

Thyroid Hormones

70
Q

Which hormone(s) are released from parent cells by exocytosis?

A

Peptide Hormone
Catecholamines

71
Q

Which hormone(s) are released from parent cells by simple diffusion?

A

Steroid Hormones

72
Q

Which hormone(s) are released from parent cell by transport proteins?

A

Thyroid Hormones

73
Q

Which hormone(s) are dissolved in plasma for transport through blood?

A

Peptide Hormone
Catecholamines

74
Q

Which hormone(s) are transported through blood bound to carrier proteins?

A

Steroid Hormones
Thyroid Hormones

75
Q

Which hormone(s) have a short half life?

A

Peptide Hormone
Catecholamines

76
Q

Which hormone(s) have a long half life?

A

Steroid Hormones
Thyroid Hormones

77
Q

Which hormone(s) have receptors located on the cell membrane?

A

Peptide Hormones
Catecholamines

78
Q

Which hormone(s) can have receptors in the cytoplasm, nucleus, and occasionally the membrane?

A

Steroid Hormones

79
Q

Which hormone(s) have receptors in the nucleus?

A

Thyroid Hormones

80
Q

What is the response to ligand binding of Peptide Hormones?

A

Activation of second messenger systems
May activate genes

81
Q

What is the response to ligand binding of Steroid Hormones?

A

Activation of genes for transcription and translation
May have nongenomic actions

82
Q

What is the response to ligand binding of Catecholamines?

A

Activation of second messenger systems

83
Q

What is the response to ligand binding of Thyroid Hormones?

A

Activation of genes for transcription and translation

84
Q

What is the general target response of peptide hormones?

A

Modification of existing proteins and induction of new protein synthesis

85
Q

What is the general target response of steroid and thyroid hormones?

A

Induction of new protein synthesis

86
Q

What is the general target response of catecholamines?

A

Modification of exisiting proteins

87
Q

Examples of Peptide Hormones

A

Insulin
Parathyroid Hormone

88
Q

Examples of Steroid Hormones

A

Estrogen
Androgens
Cortisol

89
Q

Examples of Catecholamines

A

Epi
NE
Dopamine

90
Q

Example of Thyroid Hormones

A

T3 and T4

91
Q

What is the behavior of Peptide Hormones?

Summary of Table

A

Made in Advance; stored in secretory vesicles
Released by exocytosis
Transported through blood dissolved in plasma
Short Half life
Receptor located on cell membrane
When receptor is bound activation of second messanger system; may activate genes
General Target Response is modification of exisiting proteins and induction of new protein synthesis

92
Q

What is the behavior of Catecholamines?

Summary of Table

A

Made in Advance; stored in secretory vesicles
Released by exocytosis
Transported through blood dissolved in plasma
Short Half life
Receptor located on cell membrane
When receptor is bound activation of second messanger system
General Target Response is modification of exisiting proteins

93
Q

What is the behavior of Steroid Hormones?

Summary of Table

A

Synthesized on demand from precursors
Released by simple diffusion
Transported through blood bound to proteins
Long Half life
Receptor located in cytoplasm and nucleus (sometimes cell membrane)
When receptor is bound activation of genes for transcription and translation; may have nongenomic actions
General Target Response is induction of new protein synthesis

94
Q

What is the behavior of Thyroid Hormones?

Summary of Table

A

Made in advance; precursor stored in secretory vesicles
Released by transport proteins
Transported through blood bound to proteins
Long Half life
Receptor located in nucleus
When receptor is bound activation of genes for transcription and translation
General Target Response is induction of new protein synthesis

95
Q

This hormoneis stored in vesicles within the cell until its stimulated to be released. Upon release, it binds to a bindingn protein to travel through the blood. It travels to its target cell and binds to an intracellular receptor. What hormone and I?
A. Estrogen
B. Insulin
C. Oxytocin
D. T3
E. Epi

A

D. T3

Polar and nonpolar characteristics

96
Q

What hormones are secreted by the hypothalamus?

A

TRH
Dopamine
CRH
GnRH
SS

97
Q

What hormones are secreted by the Anterior Pituitary?

A

TSH
FSH
LH
GH
ACTH
Prolactin

Tropic Hormones - stimulate release of hormones from target gland

98
Q

What hormones are secreted by the Posterior Pituitary?

A

ADH
Oxytocin

99
Q

What hormones are secreted by the thyroid gland?

A

T3
T4
Calcitonin

100
Q

What hormones are secreted by the Parathyroid Gland?

A

PTH

101
Q

What hormones are secreted by the Adrenal Glands?

A

Cortex: Cortisol, Aldosterone, Androgens
Medulla: Epi, NE

102
Q

What hormones are secreted by the Pancreas?

A

Insulin
Progesterone
SS

103
Q

What hormones are secreted by the Ovaries?

A

Estradiol
Progesterone
Inhibin

104
Q

What hormones are secreted by the Testes?

A

Testosterone
Inhibin

105
Q

What hormones are secreted by the Liver?

A

IGF-1

106
Q

Homeostasis is regulated through…

A

negative feedback

107
Q

What is the negative feedback loop that occurs after a person eats food?

A

Eat food → ↑Blood Glucose → Pancreas senses ↑Blood Glucose → insulin is released → insulin travels to the skeletal muscle → insulin stimulated ↑ uptake of glucose into muscle cells

The response counteracts the initial stimulus to decrease blood glucose

108
Q

Physiological Response - Driven Negative Feedback

A

Endocrine gland → Release of Hormone → Travels to target organ → Physiological Effects → Circulating component → Negative feed back on original endocrine gland

109
Q

Endocrine Axis-Driven Negative Feedback

A

Hypothalamic Neurodendocrine Neurons → Releases releasing hormone → stimulates pituitary gland → releases tropic hormone → travels to peripheral endocrine gland → releases hormone
Hormone can continue forward to target organs → physiological effects
OR
Hormone can feedback to the pituitary gland and Hypothalamic neuroendocrine neurons for negative feedback of the initial stimulus

110
Q

If TRH release stopped, what would happen to TSH?

A

↓TSH

111
Q

If TRH release stopped, what would happen to T3 and T4?

A

↓T3 and ↓T4

112
Q

If too much TSH was released what would happen to T3 and T4?

A

↑T3 and ↑T4

113
Q

If too much T3 or T4 was released, what would happen to TRH?

A

↓TRH

114
Q

If too much T3 or T4 was released, what would happen to TSH?

A

↓TRH

115
Q

What happens when less active hormones are secreted?

A

They are converted by enzymes to a more active form in tissue

116
Q

T4 is converted to…

A

T3

117
Q

Vitamin D3 is converted to…

A

1,25 (OH)2D3

118
Q

Angiotensinogen is converted to…

A

Angiotensin II

119
Q

What would happen if you blocked a key enzyme?

What’s an ACCE inhibitor and why is it used?

A

Conversion wouldn’t occur
Less active form would remain in circulation