Endocrinology Intro Flashcards
Five major types of hormones
and ex for each
- AA derived–dopamine, catecholamine and thyroid hormone
- small neuropeptides–gonadotropin rel hormone, TSH, somatostatin and vasopressin
- Large proteins–insulin, LH, parathyroid hormone
- Steroid hormones (cholesterol based)–cortisol and estrogen
- Vitamin derived— retinoids (vit a) and vit D
Which types of hormones interact with intracellular receptors
-why????
Steroids thyroid hormones vit d retinoids ****BC THEY ARE ALL POLAR****
which types of hormones interact with cell membrane surface receptors?
AA derivatives
peptide hormones
NON POLAR**
five general functions of endocrine system
- differentiation of the reproductive and CNS in dvlping fetus
- stim of growth and development during childhood and adolescence
- Coordination of the male and female reproductive systems–making sexual reproduction possible
- Maint of homeostasis
- Initiation of corrective and adaptive responses when emergency occurs
three patterns in whic hormones are secreted
- circadian or diurnal patterns
- Pulsatile or cyclic patterns–menses for ex
- Patterns that dep on levels of circulating substrates–NA, Ca, K, or the hormone itself
hormones operate within a _____ system to maintain ______
feedback system (pos or neg) homeostasis
where are steroid hormones excreted and produced (conjugated)
excreted–kidneys
prod–liver
what inactivates hormones
LIVER
peptide (or water based) hormones are excreted bY? and catabolized by?
excreted–feces or urine
catabolized–enzymes in circulation
hormone release is regulated by? (3)
give examples
- Chemical factors–blood glucose or ca levels
- Endocrine factors–one gland controlling another endo gland (pituitary gland)
- neuronal control–stress induced rel of catecholamines from adrenal medulla
two reasons hormones are released
- resp to alterations of hormones in body
2. chemical response to alterations in cellular envi (disruption in homeostasis)
what is the main role of negative feedback?
to turn off hormone that is already circulating in high amounts
hypothalamus produces_____hormones
pituitary gland produces ____ hormones
hypothal— RELEASING hormones (which stim the PG to rel its hormones)
PG–STIMULATING or TROPIC hormones (stim target organs to rel their hormones)
Growth hormone stimulates ___ to release _____
liver— that releases somatomedins
TSH stimulates ____ to relese ____
thyroid gland—T3 T4
Prolactin stimulates ____ to produce
breast—milk production
ACTH stimualtes ___ to release___
adrenal cortex—cortisol
FSH stimulates _____ to release ____
ovarian follices—Estrogen
testes–spermatogenesis
LH stimulates___ to release ____
Corpus luteum—progesterone
Testes—testosterone
list the Ant Pit GLand hormones
Growth hormone---GH TSH--thyroid stim hormone Prolactin ACTH--Adrenocorticotropic hormone FSH--follicle stim hormone LH--leutinizing hormone
ADH stimulates _____ to ____
kidneys–increase h20 absoprtion, constrict BVs
Oxytocin stimulates____ to ____
uterus to contract
breast to prod milk
Hormones of the post pit gland
ADH—anti diuretic hormone
Oxytocin
Hypothalamtic (NT) ___ inhibits ____ release from ___
dopamine
prolactin
AP gland
In primary hyper– disorder:
1. the [hormone] rel from the gland will be H/L
2. the stimulating [hormone] from PG will be H/L
EX?
hormone from target gland= HIGH
hormone from AP gland=LOW
all due to incr neg feedback from hyperactive target gland
EX: Grave’s disease
primary endo disorder is when what is malfunctioning?
*labs are in what direction?
target organ
*labs are in opposite direction
secondary and tertiary disorder is when what is malfunctioning?
*labs are in what direction
Pituitary gland (2) and hypothalmamus (3) *labs are in same direction
in secondary hyper– disorder:
1. the target organ [hormone] will be H/L
2. the stimulating [hormone] will be H/L
EX
BOTH will be HIGH
EX: Cushing’s disease (pituitary adenoma)
In primary hypo– disorder:
1. the [hormone] rel from the gland will be H/L
2. the stimulating [hormone] from PG will be H/L
EX?
- low
- high
EX: Hashimoto’s or thyroiditis
BC Loss of negative feedback from hypo-active target gland
in secondary (or tertiary) hypo– disorder:
1. the target organ [hormone] will be H/L
2. the stimulating [hormone] will be H/L
EX
BOTH will be low
EX: hypopituitarism
BC PG (or hypothalm for tertiary) not secreting enough
list the two hormones that thyroid gland produces
thyroid hormone—T3 T4
calcitonin
what hormone is secreted from parathyroid glands
PTH–parathyroid hormone
define short feedback loop
incr plasma levels of end target hormone prod neg feedback to AP aka turn off AP
define long feedback loop
incr plasma levels of end target hormone prod neg feedback to hypothalamus aka turn off hypothal
ex of POS feedback
stages of labor:
-incr in hormones of oxytocin—incr contractions
insulin is a water or lipid soluble
water
half life of water sol hormones are short or long? WHY
short
they are catabolized quickly by circulating enzymes
can water sol hormones diffuse accross PM?
NO
*they need
which type of hormones are transp bound to carrier or transp protein
lipid soluble hormones
can lipid sol hormones diffuse across PM?
yes–diffuse freely
what happens when lipid sol hormones are released from carrier proteins?
distributed throughout the body BUT only the cells with the hormone receptor for THAT specific hormone are affected
List of Peptide water soluble hormones
Growth Hormones
Insulin
Parathyroid Hormone
Prolactin
List of Glycoprotein water soluble hormones
Follicle stim hormone
Leuitinizing Hormone
TSH
List of Polypeptide water soluble hormones
Adrenocorticotropic Hormone ADH Calcitonin Endorphins Glucagon Melanocyte stim hormones Oxytocin Somatostatin (GH) TRH
List of amines water sol hormones
Epi
Norepi
List of Thyroxine lipid sol hormones
Thyroxine–T4
Triiodothyronine T3
List of steroid lipid sol hormones
Estrogen Glucocoticoids (cortisol) Mineralcorticoids (aldosterone) Progestins (progesterone) Testosterone
List of derivatives of arachidnoic acid lipid sol hormones
Leukotrienes
Prostacyclines
Prostaglandins
Thromboxane
steroids (lipid sol) hormones are derived from
cholesterol
Androgens, estrogens, progestins, glucocorticoids, mineralcorticoids, vit D, retinoids
steroids (lipid sol) hormones
where do steroid hormones bind to its recps?
cytoplasmic or nuclear receptors–intracellular
what do steroid hormones activate
Ribonucleic acid (RNA) polymerase DNA transcription
what is the first messenger
hormone– its secreted into the blood stream carrying a message to target cell
define signal transduction
signal that hormone carries
hormone binds to receptor—>membrane enzyme OR intracellular enzyme causes alterations in gene transcription–>creating a response to hormone
list the three cell surface receptors and what type of hormone activates them
G-protein linked receptors–water sol activates
ion-channel receptors
Enzyme-linked receptor aka kinases A and C—> MC
the more receptors a cell has=?
the more sensitive the cell is to that hormone
define up-regulation
low [ ] of hormones increase the number of receptors per cell OVER TIME
**think of the angelina Jolie and paparazzi ex*
define down-reg
high [ ] of hormones decrease the number of receptors/cell OVER TIME (not immediately)
where are hormone receptors located
IN or ON plasma membrane
or
in the intracellular compartment of target cell
high or low molecular wt for water sol hormones
HIGH
process by which hormone message is communicated into the target cell—-????
signal transduction
signal transduction steps (5)
- receptor activation/binding of hormone–>its recep
- Activation or a G protein (transducer) and membrane-assoc enzyme (effector enzyme)
- production of second messenger
- Activation of an intracellular enzyme—Protein kinase A or C
- Alterations in gene transcription and resulting target cell response to hormone
list hypothalamic hormones (9)
- Thyrotropin-releasig hormone
- Gonadotropin-rel hormone
- Somatostatin
- Growth hormone release hormone
- Corticotropin-releasing hormone
- substance P
- Dopamine
- Prolactin-releasing hormone
- prolactin-inhibiting hormone
Action of TRH
- target cells on pituitary
- hormone released?
action: stimulates release of thyroid-stimulating hormone
target cells: Thyrotrope cells on AP–>TSH
Action of GnRH
- target cells on pituitary
- hormone released?
action: stim rel of FSH and LH
Gonadotrope cells–>FSH and LH
target hormone and action of somatostatin
- target cells on pituitary
- hormone released?
action: inhibits release of GH and TSH
target gland: AP and GH + TSH
Action of GHRH
- target cells on pituitary
- hormone released?
stimulated rel of GH—- from AP
Stimulates Somatotrope cell–>GH released
action of corticotropin-rel hormone (CRH)
- target cells on pituitary
- hormone released?
stimulates release of adrenocorticotropic hormone from AP
Stims corticotrope cells–>ACTH and MSH
action of substance P
- target cells on pituitary
- hormone released?
inhibits synthesis and release of ACTH
Stimulates secretion of: GH, FSH, LH, prolactin
action of dopamine
inhibits synthesis and secretion of prolactin from AP
-INHIBIT lactotrope cells so prolactin not released
Action of prolactin-releasing hormone
- target cells on pituitary
- hormone released?
stim secretion of prolactin from AP
stimulates Lactotrope cells–>prolactin
action of prolactin-inhibiting hormone
- target cells on pituitary
- hormone released?
inhibits secretion of prolactin from AP
roles/action of posterior pituitary gland
- does NOT synthesize hormones
- release of two hormones/neurotransmitters—– ADH and Oxytocin
ADH
- function/controls___?
- acts on?
- effect on urine [ ]
stored in AP
- controls volume status and osmolality
- INCRS water reabsorption into blood
- causes vasoconstriction
- incr BP
acts on: V2 receptors of the renal tubules cells–INCRS their permeability–> INCRS h2O absorption into blood–> creates more concentrated urine
how does hypothal release its hormones?
through the portal system—>AP
adenohypophysis
Ant Pit
Neurohypophysis
Post Pit
what connects hypothal–AP
portal blood vessels
what connects hypothal–PP
hypothalamohypophysial tract
Hypothalamus is posterior to? and Anterior to?
b/w which ventricles
anterior to cerebellum
posterior to sella turcica
b/w third and fourth ventricle
another term for ADH
arginine vasopressin
arginine vasopressin
ADH
issue with ADH could cause what kind of urine and frequency?
lower concentrated urine and LOT of urine
bc loss of absorption
function of oxytocin
milk ejecting during lactation
uterine contractions
*may have some influence on sperm motility
what does oxytocin bind to and where
bind to myoepithelial cells—mammary tissues–>causes contraction of cells–>INCRs intramammary pressure–?INCR milk ejection
secretion of oxytocin is due to?
sucking response during breast feeding
inapp levels of ADH causes
large amts of dilute urine
ACTH:
- secretory cell type
- targets?
- functions
corticotropic cell–sec from AP
targets=adrenal gland
function= increased steroid-genesis, synthesis of adrenal proteins contributing to maint of adrenal gland
Melanocyte-stim hormone:
- secretory cell type
- targets?
- functions
Melanotropic cell from AP
targets=AP
function= promotes secretion of melanin and lipoprotein by AP—makes skin darker
Growth Hormone:
- secretory cell type
- targets?
- functions
Somatotropic cell from AP
targets=muscles bone liver
Function= regulates metabolic process related to growth and adaptation to physical and emotional stressers, muscle growth, incr liver glyconeolysis, incr fat metabolism
Prolactin:
- secretory cell type
- targets?
- functions
Lactotropic cell–AP
target=breast
function= milk production
TSH:
- secretory cell type
- targets?
- functions
thyrotropic cell comes from AP
target=thyroid gland
function=incr prod and secretion of thyroid hormone, increase iodide uptake, promotes hypertrophy and hyperplasia of thymocytes
LH:
- secretory cell type
- targets?
- functions
Gonadotropic cell from AP
target=granulosa cells in W and Steroli Cells in M
function= ovulation, progesterone production, testicular grwoth, testosterone prod
FSH:
- secretory cell type
- targets?
- functions
gonadotropic cell from AP
target=granulosa cells in W and Steroli Cells in M
function=follicle maturation, estrogen production and spermatogenesis
which hormone is resp for estrogen prod
FSH
which hormone is resp for ovualtion and progesterone production
LH
which hormone is resp for testituclar growth and testosterone production
LH
which hormone is resp for spermatogenesis
FSH
what connects hypothalamus to PG?
infindibulum
what provides the major blood supply to AP?
Hypothalamic-pituitary portal plexus
arterial supply to the AP and PP?
AP=superior hypophyseal artery
PP=inferior hypophyseal artery
explain + feedback loop
-give ex
increase in hormones causes increase in the magnitude of the effect
EX: contractions during child birth
- pos feedback occurs to amplify the change in system
- increase in oxytocin causes increase in contractions
define:
1. autocrine
2. paracrine
3. endocrine
- within cell
- b/w local cells
- b.w remote cells
three basic patterns of secretoin
- circadian or dinural
- pulsatile and cyclic
- patterns that dep on levels of circulating substrates— like NA, CA, K or hormone itself
steroids are excreted directly from_____ OR conjugated by_____
excreted by kidneys
conjugated by liver
