Endocrine Flashcards
What hormones are produced by your anterior pituitary?
- FSH
- LH
- ACTH
- TSH
- Prolactin
- Growth hormone
- MSH
What hormones are produced by your hypothalamus?
- GnRH
- CRH
- TRH
- GHRH
- Somatostatin
- Dopamine
What are examples of your protein hormones
- Insulin
- Glucagon
- Growth hormone
What is the MOA
and final effect of your water-soluble hormones?
- Utilize GPCR and 2nd messenger
2. Activates existing intracellylar enzymes via phosphorylation
What is the MOA and final effect of your lipid soluble enzymes?
- Causes transcription of genes
2. Synthesizes intracellular enzymes
In negative feed back, the final products become ____
limited.
Increased product, decreases secretion
What are examples of you positive feedback mechanism?
- Oxytocin during breastfeeding and delivery
2. Estrogen-induced LH and FSH surge during ovulation
___ refers to increase in number or receptor sensitivity
upregulation
____ refers to decrease in receptor number or sensitivity
downregulation
What are the 3 subunits of your GPCR?
- alpha
- beta
- Gamma
What is the most important subunit of your GPCR?
alpha subunits
it binds with GDP (inactivates G protein) or GTP (activates G protein)
binding of alpha subunit with GDP leads to (activation/inactivation_ of GPCR
inactivation
binding to GTP activates GPCR
What is the second messenger used in activating protein kinase A?
cAMP
Alpha subunit of G protein activates adenylate cyclase, converts ATP to cAMP, activates PKA
PKA phosphorylates proteins!
Which hypothalamic hormone does not use IP3/DAG 2nd messenger system?
CRH
What is the second messenger system used by ANP and NO?
Guanylyl cyclase
What is the second messenger system used by IGF?
Tyrosine Kinase System
Same with insulin
What is the second messenger system used by TGF beta?
Serin/Threonine Kinase
What is the second messenger system used by catecholamines?
Gi
inhibition of adenylyl cyclase, decrease camp, inhbit PKA, decrease phosphorylation
AND Gs
What is the second messenger system used by ADH (V2)?
Gs
same with CRH
pituitary hormones
What is the second messenger system used by ADH )V1)?
Gq
activates PLC, PIP, IP3/DAG, Ca and PKC release
Hypothalamic hormones
Thyroid hormones bind to what receptors prior to taking effect?
Nuclear receptor
- Aldosterone
- Testosterone
- Estrogen
- Prgesterone
- Vitamin D3
- T3/T4
Cortisol binds to what receptor before it triggers gene transcription to create new proteins
Cytoplasmic receptor
Steroid hormones = cytoplasmic receptor
A water soluble hormone that acts as steroid hormone by binding to nuclear receptor prior to gene transcription
Thyroid hormone
Pituitary gland is derived from what germ layer?
Ectoderm
Oral ectoderm
What are the basophilic cells found in the anterior pituitary gland
B FLAT
FSH, LH, ACTH, TSH, MSH
What hormones are secreted by the neural ectoderm-derived cells
Neural ectoderm = Posterior pitutary = ADH, Oxytocin
What hormone increases milk secretion?
Oxytocin
Prolactin is for milk production
Oxytocin is synthesized by what part of the body
Paraventricular nuceli of the anterior hypothalamus.
it is stored mainly in the posterior pituitary
Vasopressin is synthesized by what part of the body
supraoptic nuclei of the anterior hypothalamus,
it is stored and secreted in the posterior pituitary
[name the anterior pituitary hormone and target organ hormone]
GHRH
- GH
2. IGF-1
[name the anterior pituitary hormone and target organ hormone]
somatostatin
- Somatotropin
2. Somatomedin
[name the anterior pituitary hormone and target organ hormone]
TRH
- TSH
2. T3, T4
[name the anterior pituitary hormone and target organ hormone]
CRH
- ACTH
- GC
- MC
- Weak androgens
[name the anterior pituitary hormone and target organ hormone]
GnRH
- FSH, LH
2. Estrogen, Progesterone, testosterone
[name the anterior pituitary hormone and target organ hormone]
Dopamine
- Prolactin
2. Prolactin
If the pituitary stalk is damaged, which of the hormones will not decrease
Prolactin
What are the majority type of cells found in the anterior pituitary?
- Somatotropes 40%
2. Corticotropes 20%
What hormones found in the anterior pituitary has the same alpha unit but unique beta unit?
- TSH
- LH
- FSH
What hormones in the pituitary gland are derived from propiomelanocortin (POMC)?
- MSH
- ACTH
- Beta-lipotropin
- Beta-endorphon
Growth hormone is produced every?
2 hours
pulsatile
GH peaks after what stage of sleep?
Stage 3 or 4
To exert is effect, GH requires activation of what pathway ___
JAK2-STAT apthway
What are the indirect actions of GH?
- Increase bone length
- protein synthesis in muscles and other organs
- Increase lean body mass
- Increase organ size
What are the DIRECT actions of IGF-1?
- Increase bone length
- protein synthesis in muscles and other organs
- Increase lean body mass
- Increase organ size
Wha are the direct actions of GH?
- Increae plasma glucose
- Increase protein deposition
- Increase lipolysis
- Increase IGF-1
- Anti aging
What decreases secretion of GH?
- Hyperglycemia
- High fatty acid levels
- Aging
- Obesity
- Somatostatin
- Exogenous GH
- Somatomedin
Most common cause of growth hormone deficiency?
achondroplasi
Gigantism occurs ___ (before/after) closure of epiphyses
before
Acromegaly - after
Prolactin stimulates the synthesis of what compounds
- Lactose
- Casein
- Lipids
What hormone inhibits GnRH release?
prolactin
Inhibits ovulation, inhibits spermatogenesis
Osmoreceptors in the ____ detect ECF changes which in turn triggers ADH release
Organum Vasculosum (in the anteroventral wall of the 3rd ventricle)
What is the most potent stimulus for ADH release?
Increase in plasma osmolarity
What type of second messenger system is employed by the ADH receptors located in the blood vessel?
V1 receptor = Vasoconstrict = IP3/DAG
What type of ADH receptor is used by AQP inserting in the late distal tubule and collecting ducts?
V2 = 2 kidney = cAMP
contraction of the myoepithelial cells is due to what hormone?
oxytocin
Thyroid hormone can be stored for how many months in the follicular lumen?
3 months
What cell in the thyroid gland secrete calcitonin?
Thyroid Parafollicular Cells
What cell in the parathyroid gland produces PTH?
Chief cells
What protein is used to transport iodide to follicular lumen
Pendrin
Thyroglobulin and extrusion into follicular lumen happens in the ____ of the cell
RER, Golgi apparatus
The hydrolysis of T3 and T4 due to proteases happens in the
lysosome
What transporter causes transport of Iodide from the blood to the follicular cell
Na-I Symporter
[T3/T4]
Longer half life (6 days)
T4
[T3/T4]
has a higher affinity for binding plasma protein
T4
[T3/T4]
Has more affinity for binding to nuclear receptors
T3
[T3/T4]
onset of action is within 12 hours (fast)
T3
[T3/T4]
majority of of the hormone that is synthesized
T4
Hormone implicated for muscle vigor if increased
Thyroid hormone
What hormone, if increased, can cause somnolence
Thyroid hormone
Anterior pituirary hormone that if decreased is associated with cholesterol level increase
Thyroid Hormone
Anterior pituirary hormone that if decreased is associated with cholesterol level increase
Thyroid Hormone
___ refers to reduction of T3 and T4 level after ingesting large amount of Iodine
Wolf-Chaikoff Effect
___ refers to hyperthyroidism after ingestion of iodine in patients with goiter
Jod-basedow phenomenon
In the adrenal medulla, what is secreted more, NE or Epi?
Epi 80%
NE 20%
What enzyme is stimulated by ACTH to facilitate production of adrenocortical hormones?
cholesterol desmolase
converts cholesterol to pregnenolone
Enumerate the steps in aldosterone synthesis
- Pregnenolone
- Progesterone
- 11DOC
- Corticosterone
- Aldosterone
Remember: PP11CA
Enumerate the steps in cortisol synthesis
- Pregnenolone
- 11-OH Pregnenolone
- 17-OHprogesterone
- 11DCort
- Cort
Remember, Preg 17,17,11 Cortisol
Enumerate the steps in androstenedione synthesis
- Pregnenolon
- 17-OHpregnenolone
- DHEAS
- Androstene dione
What hormone is stimulated by angiotensin II?
Aldosterone synthase
Corticosterone to aldosterone
What is the effect of aldosterone to eNACs?
increases transport of ENaCs from cytoplasm to cell membrane
What hormone has the greatest effect on Na excretion?
Aldosterone
What hormone has the greatest effect on plasma osmolality?
ADH
Cortisol is highest when?
before waking up
What are the carbohydrate effects of cortisol?
- Stimulates gluconeogenesis
- Increases protein catabolism
- Decreases glucose utilization and insulin sensitivity of adipose tissue
What are the protein effects of cortisol?
- decrease cellular proteins
- Increase blood amino acids
- Increase liver and plasma proteins
What are the fat effects of cortisol?
Increase lopolysis
Cortisol induces the synthesis of what compound that inhibits phospolipase A2 in return
Lipocortin
Exogenous glucocorticoids inhibit the action of what _____
NF-KB
factor-KB
How does cortisol maintain vascular responsiveness to catecholamines?
- Upregulates alpha 1 receptor on arterioles
- Increase Epi vasoconstrictor effect
- Increases BP
How does cortisol inhibit bone formation?
- Inhibits type 1 collage
- decrease formation new bone by osteoblast
- decrease Ca absorption
[Diagnose]
hypotension, hyperkalemia, metabolic acidosis
hypoglycemia, anorexia, weight loss, weakness
decreased pubic hair and axillary harir
hyperpigmentation
Addison disease
- Low aldosterone
- Low cortisol
- Low weak androgen
- Hyperpigmentation
[Diagnose]
Hypertension
Hypokalemia
Metabolic alkalosis
Decreased renin
Conn Syndrome
[Diagnose]
Virilization in women
pseudoprecocious puberty in men, early acceleration of linear growth
21-beta hydroxylase deficiency
What hormones are secreted by the beta cells in the Islet of langerhans?
- Insulin
- Amylin
central islet
What hormones are secreted by the alpha cells in the Islet of langerhans?
- Glucagon
outer rim of islet
What hormones are secreted by the delta cells in the Islet of langerhans?
Somatostatin
intermixed in the islet
What hormones are secreted by the F cells in the Islet of langerhans?
Pancreatic polypeptide
What are the actions of glucagon?
- Glycogenolysis, Gluconeogenesis
- Lipolysis
- Inc urea production
- Inc insulin
What is the half life of insulin?
6 mins
What is the 2nd messenger of Insulin?
TK receptor
[Glucagon/Insulin]
What hormone will be secreted if
- High plasma AA
- High plasma FA
- High glucose
Insulin
Effects:
- Cellular glucose uptake
- Increase protein synthesis
- Lipogenesis
- In K intake
- Decrease glycogenolysis, dec gluconeogenesis
[Glucagon/Insulin]
What hormone will be secreted if
- High plasma AA
- Low plasma glucose
Glucagon
Effect:
- Glycogenolysis
- Gluconeogenesis
Physiologic secretion of growth hormone is increased by:
Hypoglycemia
What are the components of your ground substances?
- ECF
- Chondroitin sulfate
- Hyaluronic acid
What is the role of collagen fibers in the organic matrix of the bone?
- For tensile strength
What compound contributes to the compressional strength of the bones?
Calcium hydroxyapatite
What compounds are secreted by your osteoblasts?
- Collagen
2. Ground substances - calcium precipitates
What are secreted by your osteoclasts?
- Lysosomal enzymes
- Citric Acid
- Lactic Acid
99% of the bone is composed of
hydroxyapatite
Vitamin D is primarily absorbed by ___
simple diffusion
What is the active form of Vitamin D
1,25 dihydroxy-cholecalciferol (calcitriol)
What is the inactive form of vitamin D?
24,25 dihydroxy-cholecalciferol
accumulates in hypercalcemia
What electrolytes are increased by Vitamin D?
- Calcium
2. Phosphate
What cells secrete PTH
Chief Cells of the parathyroid glrand
What is the stimulus for PTH secretion?
low plasma calcium
What decrease in electrolyte causes PTH secretion (aside from Ca)
Magnesium
Hypomagnesemia that is due to ____ does not trigger PTH secretion
alcoholism
What is the stimulus for the release of calcitonin by the parafollicular C cells of the thyroid gland
high plasma Ca
PTH has/has no effect in Calcium and phosphate absorption in the stomach?
Has no effect
The full development of seminiferous duct require what hormone?
- Androgen
2. FSH
What enzyme is present in the prostate gland that converts testosterone to DHT
5-alpha redutase
Trace the path of teh semen
- Seminefrous tubules
- Epiddymis
- Vas deferens
- Ejaculatory duct
N - Urethra
- Penis
Hormone involved in reproduction and sex drive
- Melatonin
Which part of the brain controls the circadian rhythm?
- Suprachaismatic nuclei of the hypothalamus
2. Regulated by pineal gland through melatonin
FSH and LH are at their highest in what women age group?
- FSH and LH
What is the strongest androgen?
- DHT
- Testosterone
- Androstenedione
What neurotransmitters are used in erection
- Nitric Oxide
2. Ach
A low sperm count means that
<20 million sperms/mL
The sperm viability is ___ days
1-5 days
What hormone plays a role in differentiation of penis, scrotum and prostate
DHT
What hormone affects the growth of prostate
DHT
[Forms of estrogen]
Estrone is secreted by?
- Adrenal cortex
2. Thecal cell
[Forms of estrogen]
Estradiol is secreted by
Ovaries
[Forms of estrogen]
Estriol is secreted by
placenta
What enzyme catalyzes the conversion of androstendione to estrone and testosterone?
Aromatase
What enzyme is stimulated by FSH?
Aromatase in the granulosa cell
What organs in the body secrete progesterone?
- Corpus luteum
- Placenta
- Adrenal cortex
- Testes
What hormone is responsible for the thinning of cervical mucus?
Estrogen
What drug can be used to reduce the incidence of hot flushes?
HRT
What hormone causes proliferation of uterus?
Estrogen
causes selective negative feedback (decrease LH) in the follicular phase
What triggers ovulation?
- Estrogen-induced LH surge
The increase in basal body temperature is due to what hormone
progesterone
What hormone increases vascularity and secretory activity of the endometrium?
progesterone
causes non-selective negative feedback (decrease both FSH andLH)
The usual location of fertilization
Ampulla of the fallopian tubes
HCG levels will week at what week AOG
week 9
HCG will start to increase at what days post ovulation
6-8 days
Declines at 20 weeks AOG
During the second and third trimester, estriol will come from
- Fetal adrenal gland
- Fetal liver
3/ Placenta
During pregnancy the GnRH level, increases/decreases?
decreases
What protein hormone that is produced by the corpus luteum of the uterus, placenta, and mammary gland
Relaxin
Relaxin is also produced by makes in which organ?
Prostate gland
What is the effect of relaxin during pregnancy?
- Relaxes pubic symphysis
2. Softens and dilates the cervix
What is the effect of relaxin in males?
- Maintains sperm motility
2. Aid in sperm penetration
What is the trigger onset of fetal labor?
fetal ACTH
What are the changes in baby’s first breath?
- Increase PaO2
- Decrease pulmonary vascular resistance
- Increased systemic vascular resistance