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ENDOCRINOLOGY > Powerpoint Notes > Flashcards

Powerpoint Notes Flashcards

1
Q

hormone

A

Hormones are chemical messengers synthesized by cells of endocrine glands or tissues, secreted into the bloodstream, and act on specific target tissues to evoke a specific physiological response.

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2
Q

hormones are _____ in circulation and act on _____ target cells and tissue

A

transported
distant

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3
Q

hormones affect _____ with highly ______ receptors which _____ and ______ with hormone

A

target cells
specific
recognize and bind

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4
Q

Classic endocrine signaling

A

hormones are released into blood and lymphatic channels and circulate throughout the body to affect distant target cells

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5
Q

Intracrine signaling

A

Synthesizing cell > Synthesizing cell
Signal affects within cells
non-classical local

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6
Q

Neurocrine signaling

A

(or neural transmission or synaptic action)
Axon of presynaptic cell >Synapse > Postsynaptic target cell
non-endocrine signaling

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7
Q

Exocrine signaling

A

cells secrete signaling molecules into into lumen of gut

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8
Q

Ectocrine (pheromones)

A

One organism releases a substance  causes a response in another organism
• Lee-Boot effect: Crowded female mice become anestrous when no males are present.
• Bruce effect: A newly mated female mouse will abort if placed with a strange male (not the previous mate)
• Dormitory effect: menstrual synchrony in all-females living groups

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9
Q

Conclusion of Berthold’s experiment.

A

Presence of a testes is needed to maintain male behavioral and physiological functions.

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10
Q

Male behavior: neural or hormonal regulation? (Berthold’s)

A

Hormonal – secretory, blood-born product of the testes determines rooster characteristics.

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11
Q

Design an experiment to test your hypothesis.

(berthold, male hormonal behavior)

A

(1) Cut nerves of testes, roosters have normal appearance, development, and behavior – suggest NOT neural regulation. (2) Nerve re-connecting is nearly impossible.

Berthold’s follow-up experiment demonstrated that a testes-derived product exerts these effects in roosters:
Instead of replacing testes, replace extraction of testes.

Testes release an agent that may have direct effects or indirect effects
(activate a stimulatory effect/agent or remove an inhibitory effect/agent).

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12
Q

compensatory hypertrophy

A

Hormones released from the testis (testosterone and inhibin) exert negative feedback on pituitary cells to restrain pituitary hormone release.

Lower than normal levels of testicular hormones stimulate the anterior pituitary hormone (FSH and LH) release, stimulate testicular growth and enlargement of the testis.

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13
Q

what was bertholds (father of endocrinology) ultimate conclusion?

A

secretory, blood-borne product of the testes determines rooster characteristics.

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14
Q

Conclusion of Starling and Bayliss’ experiment

A

Exp 1: Introduce acid into a denervated but vascularized section of the jejunum (part of small intestine) caused flow of pancreatic juice; which does not require nerves.

Exp 2: Introduce acid into an isolated piece of jejunum (part of small intestine).
Extracts of jejunum produced similar effects on pancreatic secretion.

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15
Q 
Pancreatic secretion (enzyme and HCO3-): neural or hormonal regulation? 
Explain. (Starling and Bayliss’)
A

Hormonal regulation. Nerve is not necessary.
A substance is liberated by the mucosa of the small intestine, gets into the blood, reaches the pancreas, stimulates the flow of pancreatic juice.

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16
Q

Banting and Best’s experiment

A

isolated insulin reduced blood glucose levels in a diabetic dog, whose pancreas had been surgically removed. (discovered insulin)
Obtained extracts of pancreatic Islets => Insulin

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17
Q

What did Otto Loewi demonstrate?

A

demonstrated neurons transmit using a chemical messenger in 1921
Vagus nerve releases substances (acetylcholine) causes relaxation of cardiac muscle contraction

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18
Q

Conclusion of Loewi’s experiment

A

After stimulation, the vagus nerve releases acetylcholine on cardia muscle (also release into the media), which causes relaxation of cardiac muscle contraction.

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19
Q

Heart rate (also cardiac muscle contraction): neural or hormonal regulation?

Explain.

A

Neurotransmitter – does not get into circulation.

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20
Q

Claude Bernard stance on homeostasis

A

A constant internal environment is the condition of an independent life

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21
Q

Walter Cannon

A

Coined the phrase “Homeostasis

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22
Q

Compartments of body fluids

A

60% of body mass

Intracellular (2/3) and extracellular (1/3)

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23
Q

how are intra and extracellular fluid similar

A

Both have: metabolic substrates and nutrients (sugar, fatty acids, amino acids), inoganic (electrolytes) and organic ions, metabolites, minerals, O2, CO2 .

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24
Q

How are componnents of intra and extracellular fluids different

A

Extracellular fluid: extracellular matrix (proteins, polysaccarides, etc).

Intracellular fluid: proteins important in regulating cellular growth and metabolism, and cofactors (vitamins needed for enzyme function).

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25
Q

What are the two fluids that constitute the extracellular fluid? Are they same or different?

A

Interstitial fluid (75-80% of extracellular fluid) and plasma (20-25% of extracellular fluid).

Except for protein concentration is much higher in the plasma, two fluids are almost identical in composition.

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26
Q

What physiological variables need to be maintained in mammals?

A

1) Concentration of nutrients and waste products
2) Concentration of O2 and CO2
3) Concentration of salt and other electrolytes
4) pH of the internal environment
5) Volume and pressure of the internal fluid
6) Internal temperature

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27
Q

components of maintaining homeostasis

A

Variable, set point, inputs and outputs, receptors, effectors

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28
Q

Neg and Pos feedback stimulus (endocrine)

A

variable is out of the optimal range of set point.

For example: stimulatory factor causes an increase in secretion or

activity of a hormone on its target tissue.

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29
Q

Neg fdback endocrine responce

A

Effector target organ (secretion or metabolite) inhibitory control of hormone secretion

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30
Q

Pos fdback endocrine responce

A

stimulatory responce

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31
Q

Pos fdback endocrine results

A

maintain effects of stimulus factor explosive output events

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32
Q

Pos fdback endocrine significance

A

amplification of an endocrine signal; accelerates a process

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33
Q

Neg fdback endocrine results

A

Turn off effects of stimulatory factor (shuts the system off)

decrease in the magnitude of the stimulus

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34
Q

neg fdback significance

A

prevents from getting out of control

maintain at constant (baseline) level

maintain homeostasis

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35
Q

explain positive feedback in regards to
LH Surge and Ovulation

A

Increased LH secretion stimulates estrogen production from the ovary which through positive feedback leads to the midcycle LH surge that causes ovulation.(hypo and ant. pit.)

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36
Q

positive feedback (Parturition)

A

Oxytocin release is stimulated by neural inputs to the hypothalamus from cervical receptors during late pregnancy (dilation of the cervix), increasing uterine contractions.

A series of positive-feedback events involving neural and chemical cues promotes the cascade of uterine contractions (smooth muscle) during childbirth.

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37
Q

Feedforward regulation

A

anticipates a change

initiates an adaptive response before variable is being changed

happens before homeostasis has been disrupted

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38
Q

Feedforward regulation significance

A

speeds up homeostatic response

minimizes fluctuations, reduces the amount of deviation for the set point

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39
Q

example of One single gland that secretes multiple hormones

A

Presence of different types of endocrine cells in the same gland (testis: sertoli cells – inhibin, Leydig cells – testosterone; pancreas: insulin, glucagon, somatostatin; thyroid gland: thyroid hormones, calcitonin)

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40
Q

One hormone that is secreted by different organs

A

Somatostatin (from hypothalamic neurons regulates GH; from stomach epithelium regulates gastrin; from pancreas regulates insulin and glucagon)

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41
Q

One endocrine organ regulates another, which may then reciprocally regulate the first or regulate a third organ.

A

Hypothalamus-pituitary-gonads/thyroid/adrenal cortex/liver/breasts

Angiotensin (liver) – aldosterone (adrenal cortex) – kidney tubule

Parathormone (parathyroid) – Vit D (kidney) – intestine

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42
Q

types of peptide horomones

A

insulin, gastrin, vasopressin,

growth hormone, prolactin,

many hypothalamic releasing hormones

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43
Q

peptide horomone biochemistry

A

short chains of linked amino acids

Amino end (NH2) = N-terminal group;

Carboxy end (COOH) = C-terminal group

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44
Q

*1st step of insulin*

how does Modification of preproinsulin into mature insulin occur

A

via processing through the secretory pathway

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45
Q

The conversion of the nascent preproinsulin molecule into proinsulin in the RER (rough ER) is accompanied by….

A

removal of the signal peptide and formation of disulfide bonds.

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46
Q

After sorting through the Golgi is completed, proinsulin is converted to insulin within …..

A

the immature secretory vesicles through the actions of the prohormone convertases (Any of several enzymes that convert a compound into smaller, biologically-active compounds).

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47
Q

*final insulin step*

Mature insulin is then retained in the ___________, and is eventually stored within the ____________. Both insulin and the inactive C chain peptide are released via ________.

A

immature secretory granule

mature secretory granule

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48
Q

Amines

A

amino acid-derived hormones

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49
Q

Catecholamines

A
  • Derivatives of amino acid tyrosine
  • INCLUDE: Dopamine (hypothalamus); epinephrine and norepinephrine (adrenal medulla)
  • Water-soluble (hydrophilic)
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50
Q

Thyroid hormones

A

INCLUDE: Thyroxine and Triiodothyronine

  • Derivatives of amino acid tyrosine
  • Unique since inorganic iodine ion is incorporated into structure
  • Lipid-soluble (lipophilic)
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51
Q

Indolamines (hormone melatonin)

A
  • Derivatives of amino acid tryptophan
  • Precursor to melatonin is serotonin (a neurotransmitter derived from the amino acid tryptophan; is water-soluble)
  • Synthesis and secretion of melatonin from the pineal gland is affected by light exposure to the eyes
  • Lipid-soluble
  • Membrane receptor
  • Amine
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52
Q

Steroid Hormones

A

- Lipid-derived hormones

  • Derived from cholesterol
  • Gonadal or adrenal cortex origin,

includes Adrenal cortex – corticoid hormones

Glucocorticoids e.g. cortisol

Mineralocorticoids e.g. aldosterone

Kidney - 1,25-dihydroxyvitamin D (Ca2+ balance)

Gonads -

Progestin steroid hormones (e.g progesterone, pregnenolone)

Androgen steroid hormones (e.g. testosterone, 5-DHT)

Estrogen steroid hormones (e.g. 17β-estradiol, estrone)

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53
Q

Progestin steroid hormones

A

progesterone, pregnenolone

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54
Q

Androgen steroid hormones

A

testosterone, 5-DHT

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55
Q

Estrogen steroid hormones

A

17β-estradiol, estrone

56
Q

what kind of horomone are Eicosanoids

A

lipid-derived

57
Q

Eicosanoids

A

Generally function as paracrine signals

  • Coupled to endocrine signals by stimulating synthesis of hormones (such as testosterone and corticosteroids)
  • Diverse functions: blood clotting (prostacyclins and thromboxanes), induction of inflammation and fever (prostaglandins and leukotrienes), smooth muscle contraction, vasodilation, vasoconstriction, and bone remodeling (prostaglandins)
  • Increase inflammation, regulate immunity (leukocytes recruitment, cytokine production, antibody formation, cell differentiation, cell proliferation, migration and antigen presentation)
58
Q

Arachidonic acid

A

a polyunsaturated fatty acid present in the phospholipids of membranes of the body’s cells, and is abundant in the brain, muscles, and liver.

lipid-derived horomones derived from them

59
Q

Aspirin-like drugs suppress inflammation by ________

A

inhibiting prostaglandin (an eicosanoid) synthesis.

60
Q

Endocannabinoids

A
  • signaling molecules
  • Two most biologically active endocannibanoids are anandamide and 2-arachidonoylglycerol (2-AG).

–neuromodulatory lipids produced by the brain (fatty acid neurotransmitters)

–Chemically similar to cannabinoids (Δ9-tetrahydrocannabinol THC and cannabidiol CBD) found in cannabis plant (such as Marijuana)

• stimulate appetite, pain-sensation, immune response, blood pressure, stress, mood, memory, sleep, and thermoregulation.

61
Q

Peptide hormones - solubility?

A
  • Water-soluble (hydrophilic)
  • Do not passively permeate cells by diffusion through plasma membrane
  • typically interact with cell surface membrane receptors, then coupled to activation of intracellular signal transduction pathways
62
Q

Amines/ thyroid horomone solubility

A
  • Lipid-soluble (lipophilic)
  • Typically interact with a cytosolic or nuclear receptor
63
Q

Amine/Catecholamines solubility

A
  • Water-soluble (hydrophilic)
  • typically interact with cell surface membrane receptors
64
Q

amine/Indolamines specifically serotonin solubility

A
  • Water-soluble neurotransmitter
  • packaged into vesicles prior to export
65
Q

amine / Melatonin solubility

A
  • Lipid-soluble (high lipid solubility; low water solubility)
  • Leaves pineal gland via passive diffusion
  • Binds to cell surface membrane receptors
66
Q

Peptide hormones synthesis

A

Typical protein synthesis - synthesized as preprohormones; prohormones (ER)

Initial events occur within the secretory cell – convert large gene products to smaller secretory forms.

Once secreted, a peptide encounter peptidases which inactivate the peptide or convert it to forms with different biological activities.

67
Q

how can Hormone isoforms arise?

A

from differential splicing of mRNA (separate gene products) or post-transcriptional or post-translational modifications (sulfation, glycosylation, etc.)

68
Q

POMC

A

ex of multiple horomones being produced from one gene transcript

Depending on what pituitary cell type expresses it, can be converted different active hormones

69
Q

amines / Thyroid hormones synthesis

A

Synthesized on large proteinaceous substrate in lumen of thyroid

Synthesized on thyroglobulin (large proteinaceous substrate) in lumen of thyroid

70
Q

lipid derived / Steroid hormones synthesis

A

Synthesis occurs in smooth ER and lipid-rich cells of gonads and adrenal gland

Requires numerous complex, multi-enzyme synthetic pathways (both cytoplasmic and mitochondrial)

71
Q

Steroid hormone synthesis from cholesterol

A

Following import cholesterol into mitochondria via transmembrane steroidogenic acute regulatory (StAR) transporters, cholesterol is converted into pregnenolone.

Pregnenolone is converted to progesterone in the smooth ER. The smooth ER of sex steroid producing tissues, such as the testes and ovaries, convert progesterone into sex steroids, which diffuse into the blood stream. Corticosteroids, such as aldosterone and cortisol, require further processing by the mitochondria prior to release by adrenal cortex cells.

72
Q

synthesis of sex steroids

A

Pregnenolone is converted to progesterone in the smooth ER. The smooth ER of sex steroid producing tissues, such as the testes and ovaries, convert progesterone into sex steroids, which diffuse into the blood stream. Corticosteroids, such as aldosterone and cortisol, require further processing by the mitochondria prior to release by adrenal cortex cells.

73
Q

Eicosanoid hormone biosynthesis pathways

A

Arachidonic acid is synthesized by the action of phospholipase A2 (PLA2) on smooth ER membrane phospholipids.

Lipoxygenases convert arachidonic acid into leukotrienes, and cyclooxygenases use arachidonic acid to generate prostaglandins, thromboxanes, and prostacyclins.

Whereas anti-inflammatory steroids inhibit the synthesis of all eicosanoids by inhibiting PLA2 activity, non-steroidal anti-inflammatory drugs (NSAIDS) specifically inhibit the synthesis of eicosanid products generated by COX enzymes.

74
Q

endocannabinoids synthesis (lipid derived)

A

by cleavage of phospholipid precursors that are present in cellular membranes

75
Q

C-peptide

A

a short chain of amino acids that is released into the blood as a byproduct of the formation of insulin by the pancreas.

76
Q

When insulin is released from the beta cells into the blood in response to increased levels of glucose, equal amounts of _____ are also released.

A

c-peptide

77
Q

Peptide hormone secretion

A

Packaged into secretory vesicles; released by exocytosis

Prohormones can be secreted & altered after secretion

78
Q

Insulin is degraded in the _____ after secretion which occurs pretty fast

A

liver.

c-peptide an indicate insulin level

79
Q

Secretion is regulated by

A

hormonal and neural factors.

80
Q

Regulated release secretion (peptide horomone) occurs when

A

Ca2+ enters stimulated cells

81
Q

Calcium dependent exocytosis - requires increase in

A

[Ca2+]

82
Q

Amines / Thyroid hormones secretion

A

Constitutive release secretion – minimal storage; dependent on rate of synthesis

Synthesis is regulated by synthetic enzyme activities.

83
Q

Catecholamines secretion

A

Regulated release secretion

84
Q

Serotonin secretion

A

Regulated release secretion

85
Q

Melatonin secretion

A

Constitutive release secretion

86
Q

Constitutive release secretion

A

minimal storage; dependent on rate of synthesis

87
Q

Regulated release secretion

A

occurs when Ca2+ enters stimulated cells

88
Q

Steroid hormones and endocannabinoids secretion

A

Constitutive release secretion – minimal storage; dependent on rate of synthesis

89
Q

Insulin input signal

A

increase in plasma glucose

90
Q

Glucagon input signal

A

decrease in plasma glucose

91
Q

Parathyroid hormone input signal

A

decrease in plasma calcium

92
Q

Calcitonin input signal

A

increase in plasma calcium

93
Q

Growth hormone input signal

A

increase in plasma amino acids

94
Q

Example of hormone(s) secreted;

only during special circumstance (e.g. pregnancy)

A

human chorionic gonadotropin (hCG)

95
Q

Example of hormone(s) secreted;

response to specific stimulation (e.g. suckling)

A

oxytocin

96
Q

Example of hormone(s) secreted:

in a pulsatile pattern

A

gonadotropin-releasing hormone (GnRH)

97
Q

Example of hormone(s) secreted:

with a circadian rhythmicity

A

cortisol

98
Q

Example of hormone(s) secreted:

response to stress

A

adrenal catecholamines/adrenal steroids

99
Q

Example of hormone(s) secreted:

at higher levels during pubertal maturation

A

gonadotropic hormones (FSH & LH) / gonadal hormones / growth hormone

100
Q

Functions of hormone binding globulins:

A
  1. Globulins transport hormones

• increasing solubility of hormones in blood

  1. Regulate bioavailability of hormones

• since bound hormone cannot enter cells and have physiological action

  1. Regulate metabolic clearance of hormones

• since bound hormone can not enter liver/kidney cells for degradation and excretion

  1. Storage of hormone
  • provide readily available store of hormone
  • carrier proteins extend the half-life of a hormone
101
Q

peptide circulation

A

free unbound

102
Q

amine thyroid circulation

A

Bound to carrier proteins (binding globulin)

103
Q

amine catecholamines circulation

A

free unbound

104
Q

amine Melatonin circulation. bound how?

A

~ 70-80% Bound to carrier proteins;

~ 20-30% free

105
Q

Steroid hormones circulation

A
  • Bound to carrier proteins in blood circulation (globulins)
  • Examples:
  • corticosterone binding globulin (CBG)
  • steroid hormone binding globulin (SHBG)
106
Q

Endocannabinoids circulaion

A
  • Bound to fatty acid biding proteins
107
Q

T1/2 half-life

A

Amount of time required for half the molecules to become inactivated or cleared from the circulation.

108
Q

Peptide hormones metabolism

A
  • Short T1/2
  • Inactivated by enzymes
  • Liver and/or kidney and/or target organ Internalization
109
Q

Thyroid hormones metabolism

A
  • Bound to protein carrier - longer half-life
  • Occurs in many tissues, usually by deamination
  • Deiodinating enzymes (modify T3/T4 hormones)
  • In liver, conjugation to glucuronic acid occurs à bile salts (Fig 2.9)
110
Q

Catecholamines metabolism

A
  • In liver and brain
  • catechol-O-methyl transferase (COMT) and monoamine oxidase (MAO)
111
Q

Melatonin metabolism

A
  • In liver by melatonin hydroxylase
  • Then convert to a sulfate or a glucuronide for urinary excretion
112
Q

Steroid hormones metabolism

A
  • Bound to protein carrier - longer half-life (except aldosterone)
  • Metabolism typically occurs in liver
  • Convert to steroid sulphates and steroid glucuronides (make them water soluble for excretion in urine) (Fig 2.9)
  • May be excreted with bile salts (from the bowel)
113
Q

Peptide hormones Action Mechanisms

A
  • bind to surface receptors on target cells
114
Q

Thyroid hormones Action Mechanisms

A

bind to nuclear receptors of target cells

115
Q

Catecholamines action mechanisms

A
  • bind to surface receptors
116
Q

steroid horomone action mechanisms

A

bind to intracellular receptors

117
Q

Endocannabinoids action mechanisms

A
  • bind to surface receptors
118
Q

Lipid soluble hormones action mechanisms (steroid and thyroid hormones)

A

easily pass through cell membrane, bind to cytosolic and nuclear receptors in order to regulate gene expression.

119
Q

GnRH

a. Major structural class of hormone

Solubility:

b. Synthesis
c. Secretion into portal vessel blood
d. Circulation
e. Metabolism
f. Action mechanisms

A

a. Major structural class of hormone

Peptide hormone;

Solubility – water soluble

b. Synthesis
precursor: preproGnRH

encoded by a gene

process: ribosomes – DNA à mRNA à preproGnRH

Golgi (proteolytic processing enzymes) – cleave to proGnRH and mature GnRH

c. Secretion into portal vessel blood

regulated release mechanism (in pulsatile release pattern)

d. Circulation

not bound to a carrier in blood (free form)

e. Metabolism

short half-life in blood; metabolized by peptidases, at the liver, kidney and target organ

f. Action mechanisms

membrane receptors

120
Q

Estrogen

a. Major structural class of hormone

Solubility:

b. Synthesis
c. Secretion into portal vessel blood
d. Circulation
e. Metabolism
f. Action mechanisms

A

a. Major structural class of hormone

Steroid hormone

Solubility – lipid soluble

b. Synthesis
precursor: cholesterol;
process: LH binds to G-protein coupled receptor on ovarian thecal cells; via 2nd messenger system, activates cholesterol esterase, which frees cholesterol from lipid droplets; mitochondria, smooth ER and cytoplasm – Sequential modifications of cholesterol by steroidogenic enzymes
c. Secretion into circulation

Constitutive release secretion – depends on synthesis rate, which is regulated by feedback mechanism

d. Circulation

bound to a carrier in blood (SHBG)

e. Metabolism

long half-life in blood, metabolized in the liver and kidney

f. Action mechanisms

Mainly nuclear receptors

121
Q

Dopamine

a. Major structural class of hormone

Solubility

b. Synthesis
c. Secretion into portal vessel blood
d. Circulation
e. Metabolism
f. Action mechanisms

A

a. Major structural class of hormone Amines (Catecholamines)

Solubility – water soluble

b. Synthesis

precursor: tyrosine

process: Tyrosine à L-DOPA (by tyrosine hydroxylase) à dopamine (by DOPA decarboxylase)

c. Secretion into portal vessel blood
* regulated release mechanism*
d. Circulation
* not bound to a carrier in blood*
e. Metabolism
* short half-life in blood; metabolized in the liver or the CNS by enzymes COMT and MAO*
f. Action mechanisms
* membrane receptors*

122
Q

Neuroregulators

A

include neurohoromones, neurotransmitters, neuromodulators.

usually synthesized in neurons

123
Q

Neurohormones

A
  • Synthesized and released by neural cells à circulation
  • Nonpeptidergic (dopamine) or peptidergic, these are generally hydrophilic

Synthesis - Remember preprohormone and prohormone forms for peptidergic.

Synthesis can also be enzymatically converted from tyrosine

124
Q

Neurotransmitters

A
  • Synthesized in neurons and released into synapses;
  • Peptides (i.e., substance P) or non-peptides (acetylcholine, histamine, serotonin, etc.)
125
Q

Neuromodulators

A
  • Synthesized in neural and non-neural tissues
  • Modulate neural function
  • Longer lasting, slower effects
126
Q

Cooperative activity of AMPA and NMDA receptors essential for

A

long-term potentiation

127
Q

Eicosanoids (prostaglandins etc.)

A
  • Produced by all tissues from membrane arachidonic acid
  • Work in a paracrine or autocrine manner
  • Rapidly degraded in lung
  • Eicosanoid hormones are generally lipophilic, but work by binding to cell surface receptors
128
Q

Pheromones - Intraspecific (within species) chemical messengers.

They differ from hormones by:

A

They are transmitted via the external environment.

They have a higher degree of species specificity.

They produce adjustments in the bodies of other individuals.

129
Q

Hyposecretion

A

too little horomone

130
Q

Primary Hyposecretion

A

gland destruction

decreased hormone synthesis

dietary deficiency (iodine)

131
Q

Secondary Hyposecretion

A

too little tropic hormone

132
Q

Addison’s disease

A

failure to secrete cortisol due to adrenal cortex tuberculosis

failure to secrete ACTH from pituitary gland or CRH from hypothalamus

133
Q

Hypersecretion

A

overproduction of hormone secretion

134
Q

Primary Hypersecretion

A

overproduction of hormone secretion

135
Q

secondary Hypersecretion

A

excessive stimulation by tropic hormone

136
Q

Cushing’s syndrome

A

excess cortisol secretion due to adrenal cortical tumors

excess ACTH from pituitary gland or CRH from hypothalamus

ENDOCRINOLOGY (4 decks)

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