Endocrine Flashcards
how does the endocrine system compare to the nervous system
speed, duration, messenger, target?
endocrine is:
- slower
- longer lasting
- involves hormones as messenger
- larger target (bloodstream)
what are the major endocrine glands
- pituitary gland
- pineal gland
- thyroid gland
- adrenal gland
- testes
what are the types of stimulus causing hormone release
- humoral
- hormonal
- neural
what kind of stimulation depends on particle concentration in blood
humoral
which stimulation depends on regulation from negative feedback
hormonal
which stimulation involves action potentials
neural
Steroids are ____ soluble, formed from ____, and are secreted by the _____ & _____
- lipid
- cholesterol
- adrenal cortex & gonads
Peptides are ____ soluble and consist of _____
- water
- aa chains
polypeptide hormone examples
- insulin
- glucagon
glycoprotein hormones
- FSH
- TSH
Biogenic Amines are ___ soluble, derived from _____ that are modified
- water
- amino acid chains
how are peptide hormones synthesized
DNA (nucleus) > mRNA (ribo) > Preprohormone (ER) > Prohormone (golgi) > hormone in secretory vesicle storage
what do local “hormones” act on? example?
act on self (autocrine signaling) and neightboring cells (paracrine signaling)
Eicosanoids (prostaglandins, thrombozanes, leukotrienes)
what makes a cell a target of a particular hormone
the presence of a receptor for that particular hormone
releasing hormones are produced in neurons in the hypothalamus. they are stored in vesicle inside the cells until they are released. what does this suggest about chemical nature of releasing hormones?
they’re most likely peptides
T/F: hydrophilic hormones require a transport protein to travel in blood
False
which hormones are lipid soluble
steroids
which hormones are water soluble
peptides, biogenic amines
variation of target cell response depends on what factors:
- # of receptors up/down regulated by target cell
- # of circulating hormones
- half life of hormone
- strength of hormone-receptor binding
____ effect is when hormones work together to produce a greater effect
Synergistic
examples of hormones that have synergistic effect
epinephrine and glucagon
_____ effect is when the first hormone allows action of a second hormone
Permissive
examples of hormones that have permissive effects
thyroid hormone & epinephrine
____ effect is when one hormones causes the opposite effect of another. Most are humoraly regulated
Antagonistic
hormones that have antagonistic effect are
insulin and glucagon
which hormones are produced in the hypothalamus and are stored/released from the neurohypophysis
- oxytocin
- ADH
releasing hormone and inhibiting hormones are produced and released from the
hypothalamus
glycogenolysis
breakdown of glycogen into glucose
gluconeogenesis
making glucose from non-carbohydrate sources (ie amino acids)
glycogenesis
making glycogen (to store excess glucose)
lipolysis
breakdown of triglycerides
into glycerol and fatty acids
lipogenesis
formation of triglycerides
from glycerol and fatty acids
what cells of the thyroid gland produces calcium
parafollicular cells (C cells)
the adrenal gland receives blood from
- celiac trunk
- phrenic artery
- inferior suprarenal artery
the adrenal medulla contains ____ tissue made up of ____ cells
- neural
- chromaffin cells
neural tissue of the medulla is stimulated by SNS and releases _____
epi and NE as hormones
zona glomerulosa secrete _____ (such as ____)
… effect?
- mineralocorticoids
- such as aldosterone
- regulate BP & electrolyte homeostasis
zona fasciculata secretes ____ (such as ____)
… effect?
- glucocorticoids
- cortisol
- regulate stress response, immune system, metabolism
zona reticularis secretes ____ (such as ____)
… effect?
- gonadocorticoids
- androgens
- converts to sex steroids
cholecalciferol (aka ____) is obtained via
- Vitamin D3
- diet (food and milk)
- made after conversion of precursor molecule + UV light
Vit D3 (cholecalciferol) in converted to ____ by liver enzymes. This is an ____ form.
- calcidiol
- inactive
Calcidiol is converted to ____ by the kidneys. ___ increases the rate of this.
- calcitriol
- PTH
what happens to calcitriol in the small intestine
it stimulates Ca2+ absorption into the blood
if plasma Ca2+ increases, what happens to PTH
PTH decreases
what hormone stimulates endometrium growth, secondary sex characteristics, and development of fetus?
estrogen (estradiol)
what hormone is involved with nutrient enrichment, pregnancy, and smooth muscle relaxation
progesterone
what hormone has selective inhibition of FSH
inhibin
what hormones involves secondary sex characteristics, sperm development, and sex organ development
testosterone
is pancreas an endocrine or exocrine gland
both
- endo = insulin and glucagon
- exo = digestive enzymes
which pancreatic islet cells produce insulin?
… and glucagon?
- insulin = beta cells
- glucagon = alpha cells
what happens in the alarm phase of the General Adaptation Syndrome?
- mobilize glucose reserves
- change in circulation
- increase in HR and RR
- increase in energy use by all cells
which hormones are key in the alarm phase
- GH
- glucocorticoids
- ACTH
- mineralocorticoids
- ADH
what happens in the Resistance phase of the General Adaptation Syndrome?
- mobilize remaining reserves (lipids released by adipose; AA released by muscle)
- Conserve glucose in periphery (lipolysis)
- elevate blood glucose (lipogenesis and lipolysis)
- conserve Na + H2O / Lose K+ and H+
the link between the immune system and stress is that macrophages produce IL-1 that stimulates _____
ACTH
what happens during the exhaustion phase
K+ depletion
- exhaustion of lipid reserves
- inability to produce glucocorticoids
- electrolyte imbalance
- structural or functional damage to organs
protein anabolism
synthesis of protein
from aa’s
protein catabolism
breakdown of protein
to aa’s
Addison’s disease
deficient production of cortisol (and aldosterone)
Addison’s disease Sx
- weight loss
- low blood glucose
- chronic fatigue
- muscle weakness
- loss of appetite
Cushing’s disease
excess cortisol
from adrenal or from increase in ACTH from pituitary tumor
Sx of Cushing’s disease
- hyperglycemia
- break down of muscle and bone into protein
- water and salt retention (increase in BP)
- redistribution of fat
- prone to infections and poor healing
