Endocrine Flashcards

1
Q

endocrinology

A
  • study of hormones
  • chem that go thruought the body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

hormones are responsible for what?

A
  • long term ongoing fxns of the body
  • metabolism (thyroid)
  • regulation of the internal environment as a homeostasis
  • reproduction
  • growth
  • development
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

hormones act in 3 basic ways

A
  • (1) Rates of enzymatic reactions (speeds up rxn)
  • (2) Transport of ions or molecules across cell membranes
  • (3) Gene expression and protein synthesis (Ex: growth hormone)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

cellular mechanism of action for hormones

A
  • depends on binding to target cell receptors
  • initiates biochemical responses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

hormone action must be terminated

A
  • half-life indicates length of activity
  • measure how long molecules can degrade
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

most hormones are what

A
  • peptides or proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

peptide hormone synthesis, storage, and release

A

– Preprohormone is a large, inactive precursor
– Prohormone is processed to smaller form but still inactive
– Active hormone stored in vesicle; requires signal to be released

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

transported in the blood and half-life of peptide hormones

A
  • relatively short half-life
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

cellular mechanism of action of peptide hormones

A

– Bind surface membrane receptors
– Cellular response through signal transduction system

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

steroids hormones are derived from cholesterol

A
  • Made only in a few organs
    – Adrenal cortex of adrenal gland and gonads
  • Steroid hormone synthesis and release
    – Made as needed, not stored
  • Transport in the blood and half-life of steroid hormones
    – Bind carrier proteins in blood
    – Longer half-life (example: cortisol = 69-90 minutes in blood)
  • Cellular mechanism of action of steroid hormones
    – Cytoplasmic or nuclear receptors stimulate genomic effects
    – Cell membrane receptors stimulate nongenomic repsonses
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

some hormones are derived from single amino acid

A
  • Derived from tryptophan
    – Melatonin from pineal gland
  • Derived from tyrosine
    – Single tyrosine give rise to catecholamines
    ▪ Epinephrine, norepinephrine, and dopamine
    ▪ Behave like peptide hormones
    – Two tyrosine molecules give rise to thyroid hormones
    ▪ Behave like steroid hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

stimulating hormones come from what?

A

anterior pituitary gland

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

inhibiting or releasing comes from what?

A

hypothalamus

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

anterior pituitary gland hormones

A
  • thyroid stimulating hormones (TSH)
  • luitenizing hormone (LH)
  • follicle stimulating hormone (FSH)
  • growth hormone (GH)
  • prolactin (lactation)
  • ACTH = adrenocortical tropic hormone (gets released when you’re stressed. goes to adrenocortex to release cortisol)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

primary, secondary, teritary

A
  • primary: think actual gland itself
  • secondary: think pituitary gland
  • tertiary: think hypothalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

posterior pituitary gland

A
  • anti-diuretic (vasopressin)
  • oxytocin (milk outlet and stimulates pos feedback loop in birthing)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

reflex pathways have similar components

A

– Stimulus, sensor, input signal, integration, output signal, one or more targets, & response

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

the endocrine cell is the sensor in simple endocrine reflexes

A
  • parathyroid hormone (PTH)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

many endocrine reflexes involve the what?

A

nervous system

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

neurohormones are secreted into the blood by what?

A

neurons

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

the posterior pituitary stores and releases two neurohormones

A

– Neural tissue
– Stores hormones produced in the hypothalamus
– When hypothalamus is stimulated, posterior pituitary secretes two
neurohormones: vasopressin (antidiuretic hormone (ADH) and oxytocin

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

the anterior pituitary secretes six hormones

A

– Epithelial origin, thus true endocrine gland
– Trophic hormones stimulate secretion of other hormones
– Prolactin (PRL), thyrotropin (TSH), adrenocorticotropin (ACTH), growth hormone (GH), follicle-stimulating hormone (FSH), and luteinizing hormone (LH)
– Regulated by hypothalamic hormones
▪ Somatostatin (SS) = growth hormone-inhibiting hormone

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

portal systems

A
  • encapsulation of veins
  • consists of two sets of capillaries connected in series by a vein
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

hypothalamic-hypophyseal (pituitary) portal system

A

– Hypothalamic neurons produce trophic hormones
– Released into 1st capillary bed in portal system to anterior pituitary
– Anterior pituitary endocrine cells produce trophic hormones
– Released into 2nd capillary bed in portal system to target tissues

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

what does the portal system connect?

A
  • hypothalamus and anterior pituitary
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what does the portal system ensure?

A
  • small amount of concentrated hormone is directed to its target
27
Q

growth hormone

A
  • Promotes growth of the entire body by affecting:
    – Protein formation
    – Cell multiplication
    – Cell differentiation
28
Q

physiological action of growth hormone

A

– Stimulate body growth
– Stimulates secretions of insulin-like growth factor-1
– Stimulates lipolysis
– Inhibits actions of insulin on carbohydrates and lipid metabolism

29
Q

what is the most power lipid soluble hormone?

A
  • growth hormone
30
Q

antagonist for insulin

A
  • glucagon
31
Q

stimulations of growth hormone

A
  • Decreased blood glucose
  • Decreased blood free fatty acids
  • Increased amino acids
  • Starvation or fasting, protein deficiency
  • Trauma, stress, and excitement
  • Exercise
  • Testosterone, estrogen
  • Deep sleep (stages II and IV)
  • Ghrelin (stimulates hunger/stomach releases it)
32
Q

inhibits growth hormone

A
  • Increased blood glucose
  • Increased blood free fatty acids
  • Aging
  • Obesity
  • Growth hormones (exogenous)
33
Q

adrenocorticotrophic hormone controls what?

A
  • the secretions of some adrenal hormones which
    affect metabolism of glucose, proteins, and fats
34
Q

physiological actions of ACTH

A

– Stimulates production of glucocorticoids and androgens by the adrenal cortex
– Maintains size of zona fasciculata and zona reticularis of cortex

35
Q

ACTH releases 4 hormones (superficial to deep)

A
  • aldosterone
  • cortisol
  • androgens
  • epinephrine
36
Q

ACTH cortex

A

– Zona glomerulus: Aldosterone
– Zona fasciculata: Cortisol
– Zona reticularis: Androgens

37
Q

ACTH medulla

A
  • epinephrine
38
Q

aldosterone

A
  • uptakes sodium, kicks out acid, kicks out potassium
  • Regulates blood pressure by impacting the distal convoluted tubule of kidneys
  • Renin-Angiotension-Aldosterone System
39
Q

renin

A
  • detects BP in kidneys
  • if its too low = secrete angiotension 1 (liver) = turns into angiotension 2 (lung)
40
Q

cortisol

A
  • “Stress” hormone
  • Stimulates gluconeogenesis
  • Increases liver and plasma proteins
    – Muscle anabolism
  • Mobilization of fatty acids
41
Q

androgens

A
  • Several moderately active male sex hormones are
    continuously secreted by the adrenal cortex, especially during fetal life
  • Progesterone and estrogens (female sex hormones) are secreted within minute quantities.
42
Q

epinephrine

A
  • Neurohormone & neurotransmitter released in post ganglionic
    sympathetic fibers
    – Also secreted by adrenal medulla
  • Are post ganglionic sympathetic fibers of the autonomic nervous system part of the endocrine system? YES
43
Q

thyroid stimulating hormone

A
  • Controls the secretion rate of thyroxine (T4) and
    triiodothyronine (T3) by the thyroid gland
    – These hormones control the rate of most (if not all) intracellular chemical reactions in the body (i.e. METABOLISM)
    ▪ Functions of the two hormones are the same
    – T4 is more common
    ▪ 93% of metabolically active hormone
    ▪ iodine is required to formulate T4
    – T3 is more potent
    ▪ T3 can produce more powerful physiological effects
44
Q

prolactin

A
  • promotes mammary gland development and milk production
45
Q

follicle stimulating hormone and luteinizing hormone

A
  • Controls growth of ovaries and testis
  • Control reproductive endocrinology activities
46
Q

FSH

A

▪ Stimulates development of ovarian follicles
▪ Regulates spermatogenesis in the testis

47
Q

LH

A

▪ Causes ovulation and formation of corpus luteum in the ovary
▪ Stimulates production of estrogen and progesterone by the ovary
▪ Stimulates testosterone production by the testis

48
Q

antidiuretic hormone

A
  • AKA vasopressin
  • Controls the rate of water excretion into the urine within the collecting ducts of the nephron
    – Thus helping the control of concentration of water in the body fluids
49
Q

oxytocin

A
  • Female Activity: Helps express milk from the glands of the breast to the nipples during suckling
    – Helps in delivery of the baby at the end of gestation
  • Male Activity
    ▪ Some research suggest it’s associated with male ejaculation and sexual
    desire in both sexes.
    ▪ Not enough research to make strong claim
50
Q

hormones associated with the GI system

A
  • Ghrelin
    – Released by the stomach
    – Stimulates hunger and appetite
  • Leptin
    – Released by adipose tissue
    – Stimulates “full” sensation
51
Q

the pancrease secretes what?

A
  • insulin and glucagon
  • beta cells: insulin (high BS stimulates insulin)
  • alpha cells: glucagon
52
Q

the insulin to glucagon raio regulates metabolism

A

– In the fed state (eating), insulin dominates
– In the fasting state, glucagon dominates

53
Q

insulin

A
  • Insulin (break down glucose) promotes anabolism
    – Insulin binds to tyrosine kinase receptors
    ▪ Activated
    – Insulin lowers plasma glucose
    ▪ 1. Insulin increases glucose transport into insulin-sensitive cells
    ▪ 2. Insulin enhances utilization and storage of glucose
    ▪ 3. Insulin promotes fat synthesis
54
Q

glucagon

A
  • Glucagon is dominant in the fasted state
    – Generally antagonist to insulin
    – Glucagon prevents hypoglycemia
    ▪ Liver is primary target
    ▪ Stimulates glycogenolysis and gluconeogenesis
    – Release stimulated by low blood glucose levels
  • increase sugar levels
55
Q

parathyroid hormone

A
  • released by parathyroid to increase blood calcium levels
56
Q

calcitonin

A
  • released by thyroid to decrease blood calcium levels
  • tones the bone
  • brings Ca+ into the bone
57
Q

hematological modulated hormones

A
  • Erythropoietin: detects all blood cells that go thru the kidney
    – Kidney releasing hormone to stimulating production of red blood cells
  • Atrial Natriuretic Peptide
    – Heart releasing hormone to lower blood pressure and control electrolyte homeostatis
58
Q

long-loop negative feedback

A

– Peripheral endocrine gland produces hormone that suppresses secretion of anterior pituitary and hypothalamic trophic hormones
– Most dominant feedback mechanism

59
Q

short-loop negative feedback

A

– Pituitary hormone suppresses hypothalamic trophic hormone production
– Secondary feedback mechanism

60
Q

ultra-short-loop negative feedback loop

A

– Occurs in hypothalamus and pituitary
– Autocrine or paracrine signals to regulate secretion

61
Q

hormone interactions

A
  • In synergism, the effect of interacting hormones is more than additive
  • A permissive hormone allows another hormone to exert its full effect
    – Permissiveness
  • Antagonistic hormones have opposing effects
    – One substance opposes the action of another
    – Competitive inhibitors vs. functional antagonists
62
Q

down-regulation

A
  • sensitivity issues
    – Decreased number of receptors in response to abnormally high hormone levels
    – Target cell is attempting to diminish its responsiveness to the excess hormone
    – Hyperinsulinemia
63
Q

receptor and signal transduction

A

– Missing or nonfunctional receptors
– Cells fail to respond or respond inappropriately to hormone signals

64
Q

hormone evolution

A
  • Evolutionary conservation of hormone function
  • Proteomics determines physiological role of hormones
    • Example: Calcitonin
  • Vestigial structures have lost functionality in humans
    – Example: Intermediate lobe of pituitary and melanocyte-stimulating hormone
  • Comparative endocrinology is the study of endocrinology in non-humans to reveal possible functionality in humans
    – Example: pineal gland and melatonin