Endocrinology Flashcards

1
Q

chemical substance that is produced and secreted into the blood by an organ or tissue and that has a specific effect on a target tissue located away from the site of its origin.

A

Hormone*

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

Prostaglandins?

A

-influences neighboring cells
-autocrine and paracrine function
-very short half-life

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

Exocrine or endocrine gland?

Secretory products are
released on to “external surfaces”
* e.g. Sweat, Salivary gland

A

Exocrine gland

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

Exocrine or endocrine gland?

-Secretory products into the “blood stream”
-transport them to specific target tissues

A

Endocrine gland

-Upon reaching the specific target
* Secretary product alters the function of target
cell

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

❖ Characteristics of endocrine hormones and their effects:

Effects are not on and off but graded…

A

up or down

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

❖ Characteristics of endocrine hormones and their effects:

Secretion is not constant but usually occurs in _______.

A

pulses

-Provocative tests are required (stimulates max release)

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

❖ Characteristics of endocrine hormones and their effects:

Effects of the hormones continue after…

A

the hormone is gone

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

❖ Characteristics of endocrine hormones and their effects:

Hormones don’t act alone. What are some examples?

A

blood glucose; insulin and glucagon

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

❖ Characteristics of endocrine hormones and their effects:

Some hormones do similar things at….

A

different rates

Glucagon & cortisol: increases [glucose]blood, glucagon: rapid & temporary v. cortisol: slow & sustained

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

❖ Characteristics of endocrine hormones and their effects:

Some hormones accomplish similar results with different…

A

tissue specificities

-Epi & glucagon on glycogenolysis. Epi: muscle v. Glucagon: best on liver

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

❖ Characteristics of endocrine hormones and their effects:

Sometimes the tissue determines the _________ of the response.

A

quality

ex: EPI- glycogenolysis in muscle( increases glucose) & lipolysis in adipose (increases FA)

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

❖ Characteristics of endocrine hormones and their effects:

Hormone don’t always fit the ________ definition.

A

classical

ex: e.g. ACTH (mostly released in the adrenal glands but also in the brain)

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

What are the physiologic functions of hormones?

A

-Maintenance of
internal milieu
-Production
-Growth and
Development
-Energy Metabolism

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

How many amino acids are peptides? Proteins?

A

peptides = <100
proteins = >100

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

Where does ADH come from?

A

hypothalamus

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

Hormone type:

-Water soluble and do not require transport proteins
-short half-life
-synthesized from amino acids

A

➢Protein /Peptide Hormones

e.g. insulin, glucagon

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

Hormone type:

Synthesized from cholesterol
* Lipid soluble and require transport proteins
– Only free-form is biologically-active
* Long half life

A

Steroid hormones

e.g. testosterone, aldosterone

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

Hormone type:

derived from tyrosine

A

Amino acid-based hormones

e.g. Thyroxine, epinephrine (catecholamine)

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

_____________ stimulates transcription of sodium/potassium ATPase

A

aldosterone

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

What causes hormones to have different mechanisms of action?

A

due to structural and solubility differences.

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

-large & H2O soluble
➡ tend to remain in the circulation
✴These hormones bind to EXTRACELLULAR RECEPTORS activating a protein cascade
➢ Involves membrane receptor activation & a secondary messenger

A

Protein-based hormones

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

Cross membranes –> bind DIRECTLY to their intracellular targets.
✴ Hormone-Receptor complex DIRECTLY activates TRANSCRIPTION.

A

Steroid hormones: lipophilic

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

❖ Hormone secretion occurs in _______ or ________ rather than in a continuous,
constant manner

A

bursts, pulses

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

Only a small portion of the hormone is removed by the target tissue;
most are cleared by

A

the liver or kidneys

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

__________ hormones: actions are specific for another endocrine gland

A

Tropic

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

___________ hormones: Directly stimulate target cells to induce
effects.

A

❖ Non-tropic

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

__________ hormone: Works on organ or tissues to enhance cellular “growth, differentiation & survival”

A

Trophic

(bigger word, bigger tissues)

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

Major function of the anterior pituitary? posterior pituitary?

A

anterior pituitary- makes hormones

posterior pituitary- storage of hypothalamus hormones.

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

The hypothalamus is Connected to pituitary via a cluster of nerves & blood vessels called the pituitary _______

A

stalk

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

The hypothalamus produces what factors?

A

releasing factors
(RF) & inhibiting factors (IF).

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

What is PVN?

A

paraventricular nucleus

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

What is SON?

A

supraoptic nucleus

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

Composed of nests of different cell types that secrete different hormones
– Hormone secretion is controlled by the hypothalamus (Tropic hormones)

A

Adenohypophysis (anterior lobe)

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

Adenohypophysis (anterior lobe):

– Hormones: FLAT PEG?

A

FSH, LH, ACTH, TSH
Prolactin, Endorphins, GH

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

Does NOT synthesize any hormones.
– Serves as a storage area for ADH (vasopressin) and Oxytocin –produced by hypothalamus.

A

Neurohypophysis (posterior lobe)

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

“Stimulus” of ADH?

A
  1. Increased extracellular fluid osmolality
  2. Declining blood pressure or volume
  3. Non-specific stimuli: trauma, anxiety, nicotine, barbiturate anesthetics
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Vasopressin is primarily synthesized in the _______

A

SON

-ADH is transported to the P-Pit & stored in axon terminals

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

“Effect” of ADH?

A
  1. ADH increases the water permeability of CD (V2 receptor & cAMP)
  2. Contracts vascular smooth muscle (V1 receptor, IP3)

-increased aquaporin expression in the nephron

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

Oxytocin is secreted by the _____.***

A

PVN

-Short half life (3-5 min)

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

Where is oxytocin stored/released?

A

by the posterior pituitary.

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

Where are the major sites of action of oxytocin?

A

Smooth muscle
1) Uterus 2) Mammary gland
-Critical role in lactation & during labor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

1) stimulates the epithelial cells surrounding the mammary glands
(Milk ejection)
2) Uterine smooth muscle contraction
3) Psychological function: as a neurotransmitter

A

OXYTOCIN

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

Stimulus for oxytocin release…

A
  1. Suckling: sensory receptor send afferent signal to the CNS generating AP in neurons with nerve endings in the p-Pit which
    release oxytocin
  2. Distention of uterus & cervix: during pregnancy & movements of the infant result in transmission of neural signals to the CNS.
    Subsequent AP release oxytocin from the p-Pit
  3. Stimulation of the cervix during sexual intercourse also sends signals to release oxytocin from the P-pit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

Frequency & force of oxytocin-induced contractions sharply
enhanced in the presence of ___________.

A

estrogen

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

Role of Estrogen?*

A

1) Induces oxytocin receptors
2) Induces uterine prostaglandin synthetase

46
Q

Produced by the lactotroph cells in the anterior pituitary

A

PROLACTIN [LACTOGENIC HORMONE]

47
Q

Stimulus of Prolactin release…

A
  1. the development of breast tissue for lactation
  2. initiation and maintaining lactation
  3. synthesis of milk proteins
48
Q

What can cause hyperprolactinemia?

A

Drugs & pituitary tumors (Prolactinoma)

-Hyperprolactinemia —> Galactorrhea & Gynecomastia

49
Q

Growth hormone is secreted by ___________ cells in A. Pituitary.

A

somatotroph

50
Q

Growth hormone is controlled by _______.

A

GHRH (hypothalamus)

-Less so by somatostatin

51
Q

✴ Stimulus for GH release…

A
  1. AA (particularly Arg)
  2. Ingestion of a protein meal
  3. Starvation
  4. Hypoglycemia
  5. Exercise, stress, excitement, trauma
  6. Sleep
52
Q

How does growth hormone increase protein synthesis?

A

a) increases AA transport into cells
b) increases RNA synthesis
c) increases Ribosomal protein synthesis
d) decreases Protein catabolism

53
Q

How does Growth hormone “spare blood glucose”?

A

Stimulate lipolysis & lipid utilization
-Net result: blood glucose rises

54
Q

How does GH inhibit carbohydrate (CHO) utilization?

A

-increases glycogen deposition
-decreases cellular glucose uptake once glycogen stores are saturated

55
Q

GH stimulates the release of ____________ from liver and kidney.

A

somatomedin

(peptide growth?, insulin-like growth factor?)

56
Q

-excess GH in adults
-enlarged bones

A

Acromegaly

57
Q

excess GH pre-puberty

A

Gigantism

58
Q

– pre-puberty deficiency of GH
➡ small stature but proportionally built

A

dwarfism

59
Q

E3, placenta?

A

Estriol

60
Q

E1, (P menopause, cancer)

A

Estrone

61
Q

E2?

A

estradiol

-estrogen C-18

62
Q

What are the 3 distinct tissues of the adrenal cortex (from outside to inside)?

A

– Zona glomerulosa (G zone)
– Zona fasciculata (F zone)
– Zona reticularis (R zone)

  • Has a high lipid content and produces steroid hormones
63
Q

layer of the adrenal gland that is Composed of sheets of irregular cells with small nuclei called*
-Chromaffin cells (involved with epinephrine?)

A

Inner layer: adrenal medulla

64
Q

What are the cells associated with Chromaffin cells?*

A

Pheochromocytes, neuroendocrine cells

65
Q

The primary mineralcorticoid produced & secreted by Zona Glomerulosa

A

aldosterone

66
Q

How is aldosterone transported?

A

Transported by Albumin & Corticosteroid Binding Globulin

67
Q

What is the function of aldosterone?

A

-sodium reabsorption
-K+, H+ and Mg2+ excretion
-Regulates extracellular fluid volume
➢ increase blood volume & blood pressure via the Renin-Angiotensin system

68
Q

is a protein produced by the JGA of the kidney in response to decreased renal perfusion pressure or decreased serum Na+ levels.

A

Renin

69
Q

Renin acts on _____________ (liver) to produce angiotensin I, which is converted to angiotensin II by ACE present in the vascular endothelium of
the lung & kidney.

A

angiotensinogen

70
Q

Angiotensin II is converted to angiotensin III by an aminopeptidase. AngII
is a potent vasoconstrictor. Both AG-II & AG-III can bind to the receptor on
the target cell (in adrenal cortex) which stimulates the secretion of _________.

A

aldosterone

71
Q

What are the two ways the renin-angiotensin system increases blood pressure?

A

by vasoconstriction and increased plasma volume

72
Q

angiotensin ___ —> vasoconstriction.

A

2

73
Q

The primary glucocorticoid produced & secreted by Zona Fasciculata

A

Cortisol: Hydrocortisone

74
Q

How is cortisol transported?

A

transported bound ( >95%) to plasma proteins
(albumin & CBG)

75
Q

** a decrease in free [cortisol] in the serum stimulates hypothalamus to secrete ____________.

A

corticotropin (ACTH)

76
Q

ACTH stimulates _____________ to secrete cortisol.

A

zona fasciculata

77
Q

What converts Angiotensin II to Angiotensin III?

A

Aminopeptidase A

78
Q

What are the functions of cortisol?

A

-gluconeogenesis in liver (increase glucose)
-affects metabolism of protein and fat
-stimulates erythropoiesis
-anti-inflammatory

79
Q

How is cortisol catabolized?

A

liver & kidneys.
▪ < 2% free cortisol (active) is filtered
& excreted by kidney

80
Q

What is cortisol measured as?***

A

17 hydroxy corticosteroids

81
Q

Why is 17 hydroxy corticosteroids measured in the lab for cortisol?

A

-water soluble
-metabolized product of cortisol
-urine sample

82
Q

Target Tissues of cortisol?

A

Target tissues: kidney (glomerulus & tubule), bone marrow stem cells, hepatocytes, & adipose tissue.

83
Q

___________ are metabolites of testosterone and adrenal steroid hormones.

A

17-ketosteroids

84
Q

Adrenal Androgens:

Steroid hormones, produced by ___________.

Secretes precursors to androgens (mostly Androstenedione)

A

Zona Reticularis

85
Q

a monoamine that contains catechol and amine side chain

A

catecholamine

86
Q

Hormones produced by adrenal medulla
❖Produces ________-by hydroxylation of the tyrosine.*

e.g. Epinephrine (E), norepinephrine(NE)

A

catecholamine

87
Q

What is the function of catecholamine?*

A

▪Neurotransmitter (SNA)
▪ Increase blood pressure, heart rate, and blood sugar

88
Q

What is the stimulus of catecholamine production?*

A

▪ Released in response to pain & emotional disturbance

89
Q

How adrenal medulla hormones transported?*

A

free in blood and regulated by feedback

90
Q

Metabolites of catecholamine?*

A

metanephrine & normetanephrine
“ Vanillylmandelic acid (VMA) (enzyme: monoamine oxidase)

91
Q

Metabolism of medullary hormones:

What are the metabolites that are measured in lab?

A

-Catechol Methyltransferase (COMT)
-Monoamine oxidase (MAO)

92
Q

Hyperaldosteronism:

increased serum and urine aldosterone
-metabolic _________

A

alkalosis

increased pH due to decreased hydrogen

93
Q

Symptoms of hyperaldosteronism?

A

-fatigue and weakness
-hypertension

94
Q

Types of Hyperaldosteronism:

  • Aldosterone secreting adrenal adenoma or adrenal
    hyperplasia
  • Something wrong with the adrenal gland itself.
A

1° hyperaldosteronism (Conn’s syndrome)

-tumor/cancer

95
Q

Excessive production of renin resulting in increased
aldosterone production

A

2° hyperaldosteronism

96
Q

Hypoaldosteronism (isolated)
➢ Lack of aldosterone production could be due to:

A

-Damaged adrenal gland
▪ Decreased renin production by kidneys or
▪ G layer (G zone) enzyme deficiency

97
Q

________ is key factor to release cortisol***

A

ACTH

98
Q

➢ Decreased production of adrenal hormones
Cortisol and/or Aldosterone

A

Adrenal insufficiency (Addison’s disease)

99
Q

Types of adrenal insufficiency?

A

➢ 1° Adrenal insufficiency
▪ damaged adrenal Cortex (~ 90%)
➢ 2° Adrenal insufficiency
▪ ACTH deficiency (abnormality at the pituitary level)

100
Q

symptoms of Addison’s disease?

A

dehydration, decreased
kidney function, shock (can occur due to decreased blood pressure)

101
Q

How is ACTH effected with adrenal insufficiency?*

A

-increased with primary
-decreased with secondary

102
Q

How is plasma Na+ and aldosterone effected with adrenal insufficiency?

A

-decreased with primary
-normal with secondary

103
Q

How is H+ and K+ effected with adrenal insufficiency?

A

-increased with primary
-normal in secondary

104
Q

What is Cushing’s syndrome?

A

Hypercortisolism due to increased cortisol production by:
* adrenal gland (primary)
* increased ACTH release from pituitary (secondary)

105
Q

Cushing’s syndrome/ hypercortisolism:

ex: adenoma (only 10% cases)
* No regard for feedback from ACTH
* Labs: ↑ Fasting blood glucose (FBG), ↑ plasma cortisol, ↓ ACTH,
↑ urinary free cortisol

A

1° disease

106
Q

Cushing’s syndrome/ hypercortisolism:

hyperpituitarism (pituitary cushing’s)
– or –hyper ACTH secretion due to tumor (Ectopic cushing’s)
* Labs: ↑ FBG, ↑ plasma cortisol,↑ ACTH, ↑ urinary free cortisol

A

– 2 ° disease

107
Q

Symptoms of Cushing’s?

A

▪fat face (moon face),
▪enlarged fat between shoulder blades (buffalo hump)
▪Fat body and skinny arms and legs (centripetal fat
distribution)
▪Increased serum glucose (steroid diabetes)

108
Q

PHEOCHROMACYTOMA:

Catecholamine producing tumors arising from the __________
of adrenal _________.

A

chromaffin cells, medulla***

-Tumors lead to the production and release of large quantities of
catecholamine.*

109
Q

PHEOCHROMACYTOMA:

labs?

A

urinary metanephrines, VMA***

110
Q

PHEOCHROMACYTOMA:

symptoms?

A

Headache, periodic sweating, hypertension***