Endocrine Physiology Flashcards
Secreted by the pancreatic cells in response to an increase in blood glucose?
Insulin
Secreted by the chief cells of the parathyroid gland in response to a decrease in serum Ca?
PTH
Mechanism of hormone action:
ACTH
cAMP Mechanism
Mechanism of hormone action:
CRH
cAMP Mechanism
Mechanism of hormone action:
MSH
cAMP mechanism
Mechanism of hormone action:
PTH
cAMP Mechanism
Mechanism of hormone action:
Glucagon
cAMP Mechanism
Mechanism of hormone action:
ADH V1 Receptor
IP3 Mechanism
V1 : IP3
Mechanism of hormone action:
Oxytocin
IP3 Mechanism
Mechanism of hormone action:
ADH V2 Receptor
cAMP Mechanism
Mechanism of hormone action:
Insulin
Tyrosine Kinase
Mechanism of hormone action:
IGF-1
Tyrosine kinase
Mechanism of hormone action:
ANP
cGMP mechanism
Mechanism of hormone action:
NO
cGMP mechanism
Effect of TRH on prolactin secretion?
Increases Prolactin Secretion
- In case of Primary Hypothyroidism ( Low Thyroid Hormones, High TRH) , it is crucial to check for prolactin levels or its effects on the body.
Acts on tissues by steroid hormone mechanism ?
- Glucocorticoid
- EST ( Estrogen)
- TESTOSTERONE
- PROGESTERONE
- Aldosterone
- Vit D
- Thyroid Hormone
41/F with hypocalcemia, hyperphosphatemia, decreased urinary phosphate excretion. PTH injection increases cAMP. Diagnosis?
a. Primary Hyperparathyroidism
b. Hypoparathyroidism
c. Vit D Intoxication
d. Vit D deficiency
Hypoparathyroidism after thyroid surgery
- Not primary hyperparathyroid. The patient responded to exogenous PTH with an increased in urinary cAMP.
- Not Vit D intoxication, Hypercalcemia instead hypocalcemia
- Not Vit D deficiency. Hypocalcemia w/ Hypophosphatemia
38/M with galactorrhea and prolactinoma. Treated with bromocriptine. Therapeutic action of drug ?
Inhibits prolactin release from the anterior pituitary.
Bromocriptine is a dopamine agonist.
Hormones released from posterior pituitary? (2)
Oxytocin & ADH
Parent molecule of ACTH?
Proopiomelanocortin (POMC)
Parent molecule for B-endorphin ?
Proopiomelanocortin (POMC )
Parent molecule for A-lipotropin?
Proopiomelanocortin (POMC )
Parent molecule of B-lipotropin ?
Proopiomelanocortin (POMC )
Parent molecule of MSH?
Proopiomelanocortin (POMC )
Inhibits the secretion of growth hormone?
Somatomedin
- Inh directly and indirectly by stimulating somatostatin release
Effect of sleep on growth hormone?
Increased secretion
- Growth hormone is secreted in pulsatile fashion with a large burst occurring during sleep.
Effect of stress on growth hormone?
Increased secretion
Effect of puberty on growth hormone?
Increased secretion
Effect of starvation on growth hormone?
Increased secretion
Selective destruction of the zona glomerulosa, cause what hormone deficiency?
Aldosterone
Step in steroid hormone biosynthesis, which blocks the production of all androgenic compounds, but not the production of glucocorticoids?
17-Hydroxypregnenolone to Dehydroepiandrosterone
46/F with hirsutism, hyperglycemia, obesity, muscle wasting, and increased ACTH.
Diagnosis?
Cushing Disease - Primary overproduction of ACTH
Phosphate level that increases the conversion of 25-hydroxycholecalciferol to
1,25-dihydroxycholecalciferol ?
Hypophosphatemia
Factors that increases the conversion of 25-hydroxycholecalciferol to
1,25-dihydroxycholecalciferol ? (3)
- Hypophosphatemia
- Hypocalcemia
- PTH
PTH activates 1a- hydroxylase to convert vit D to its active form.
ACTH secretion during chronic adrenocortical insufficiency (Addison disease) ?
Increased ACTH secretion
Expected hormone levels in Graves disease?
Increased T3, T4
Low TSH
Step in steroid hormone biosynthesis stimulated ACTH?
Cholesterol to Pregnenolone via Cholesterol desmolase
Blood volume level causing increased aldosterone secretion?
Decreased blood volume
61/F with hyperthyroidism , treated with propylthiouracil. PTU inhibits oxidation of?
Iodide (I-)
PTU Inh the peroxidase enzyme, thus inhibiting the organification of iodide to I2; halting thyroid hormone synthesis.
39/M with untreated T1DM, insulin injection effect on pH?
Increased blood pH
-Before insulin, untreated DM patient will have metabolic acidosis. Upon giving insulin, ketoacid production will be decreased, thus correcting the metabolic acidosis and increasing blood pH.
Action of PTH on the Distal renal tubule ?
Stimulation of Ca 2 reabsorption in the distal tubule.
Action of PTH on the Proximal renal tubule ?
Inhibits Phosphate Reabsorption
Action of PTH on vitamin D synthesis and regulation ?
Stimulates 1-alpha hydroxylase enzyme in the renal tubules.
Pancreatic secretion with 4 subunits and tyrosine kinase activity in its receptor?
Insulin
76/ M with lung cancer. Excess urine volume , thirsty , drinks water constantly .
Labs:
- High serum Ca
- High serum Osmolarity
- Low urine osmolarity
- No change of osmolarity after ADH administration
What’s the expected ADH level?
Increased, because the elevated serum osmolarity has stimulated ADH secretion
76/ M with lung cancer. Excess urine volume , thirsty , drinks water constantly .
Labs:
- High serum Ca
- High serum Osmolarity
- Low urine osmolarity
- No change of osmolarity after ADH administration
What’s the Diagnosis?
Nephrogenic Diabetes Insipidus
💙Absent of Ineffective ADH
= No water reabsorption ( High serum osmolarity / concentrated)
= Water excreted (Low urine osmolarity/ diluted)
💙No change after ADH administration
= Nephrogenic
76/ M with lung cancer. Excess urine volume , thirsty , drinks water constantly .
Labs:
- High serum Ca
- High serum Osmolarity
- Low urine osmolarity
- No change of osmolarity after ADH administration
What’s the expected treatment?
Pamidronate - Inhibits bone resorption
Furosemide - Inhibits renal calcium reabsorption
Nephrogenic DI secondary to hypercalcemia secondary to PTHrp secretion of the lung tumor. Treatment should be directed in lowering serum Calcium.
TRH is secreted by the ______________.
Hypothalamus
HypoTRHalamus
TSH is secreted by the ______________.
Pituitary
PituiTSHary gland
T4 & T3 are secreted by _________________.
Thyroid Gland
True or False.
T3 is more active than T4.
True
True or False.
T4 is synthesized abundantly than T3.
True
1 MIT + 1 DIT = ____________
T3
1 DIT + 1 DIT = ____________
T4
In peripheral tissues T4 is converted to T3 or rT3 by what enzyme?
5’-iodinase
Inactive or Active ?
rT3
Inactive
Inhibits the Iodine pump / Na - Iodine Co- transport? (2)
- Thiocyanate
- Perchlorate Anions
The peroxidase enzyme which catalyzed the oxidation of I- to I2 is inhibited by?
PTU - Propylthiouracil
Effect in which high levels of Iodine inhibit organification and therefore inhibits the synthesis of thyroid hormone?
Wolff-Chaikoff Effect
Precursors of epinephrine?
Norepinephrine
(Pare True Love Does Not Exist To Me)
A 39/M with untreated T1 DM is brought to the ER. An injection of insulin would be expected to cause an increase in his?
Blood pH
Insulin given to DKA leads to?
Decreased Hyperventilation
Resolution of acidosis and improvement of serum bicarbonate due to IV insulin infusion
Center for thermoregulation:
a. hypothalamus
b. thalamus
c. Amygdala
Hypothalamus
Hypothalamus secretes? (6)
- CRH
- GnRH
- Dopamine
- Somatostatin
- GHRH
- TRH
Synthesized in the hypothalamus and stored & secreted in the posterior pituitary? (2)
- Oxytocin
- Vasopressin
Adrenal Insufficiency is associated with?
Hypoosmotic Volume Contraction
Derivatives of POMC? (4)
- MSH
- ACTH
- Endorphin
- Metenkephalin
Increases secretion of Oxytocin? (6)
- Dilatation of Cervix
- Suckling of the breast
- Orgasm
- Sight
- Sound
- Smell of Infant
Potent in increasing gallbladder contractility?
Cholecystokinin (CCK)
Important in the feedback mechanism of controlling hormone secretion?
Secretory Rate
Steroid hormones , Vitamin D are derived from?
Cholesterol
Actions of prolactin? (4)
- Milk production
- Inhibits ovulation
- Inhibits spermatogenesis
- Stimulates breast development together with estrogen and progesterone during puberty and pregnancy
Safety factors against edema?
- Low tissue compliance in the negative pressure ranges
- lymph flow driven by tissue pressure
- protein washout by lymph
- Decreased proteins in the interstitial fluids when lymph flow increases
Fluid to give for DKA?
NSS
Site of aldosterone secretion? (2)
- Zona glomerulosa
- Adrenal cortex
Secretin actions? (2)
- Inhibits HCl
- Increases biliary and pancreatic bicarbonate
Site of weak androgen secretion?
Adrenal Cortex
Zona reticularis
Actions of caffeine? (3)
- Inhibits all types of adenosine receptors (ARs): A1, A2A, A3, and A2B ( affects brain functions such as sleep, cognition, learning and memory)
- Inhibits phosphodiesterases (PDEs): PDE 1, PDE 4, PE5
- Promotes calcium release from intracellular stores
What is the sympathetic supply of the kidney?
Beta-1
Hyperaldosteronism eg. Conn Syndrome, is associated with which acid-base abnormality?
Metabolic alkalosis - due to increased H+ secretion to the urine
Severe water deprivation vs SIADH ?
Severe water deprivation shows an increased plasma osmolarity due to increased sweating that causes greater water loss than Na loss.
SIADH shows an decreased plasma osmolarity due to increased water reabsorption in the kidneys.
What are the adrenal gland hormones from the innermost to outermost?
- Epi
- NE
- Weak Androgens
- Cortisol
- Aldosterone
putang ENA CA
Has four subunits and tyrosine kinase activity?
Insulin
Hormone secreted in response to GIP ?
Insulin
Involved in regulation of body clock?
Melatonin
Self-limiting mechanism to control hormonal effect?
Negative feedback
Stimulates glycogenolysis?
Glucagon
Stimulates potassium influx?
Insulin
Diuretic used in the treatment of acute mountain sickness?
Acetazolamide sounds like a rock in the mountain
Half life : 2 mins short compared to renin , aldosterone, corticosterone, and DHEA.
Norepinephrine
Decreases food intake and may also increase energy expenditure.
Leptin has anorexigenic effect
Where is Acetylcholine produced?
Basal Nucleus of Meynert
Where is NE produced in the brain?
Locus Ceruleus
Where is Serotonin produced?
Raphe Nucleus
( Sir Raphe)
Where is dopamine produced?
Ventral Tegmentum of Substantia Nigra
Where is GABA produced?
Nucleus Accumbens
How much body water is lost in the feces during prolonged heavy exercise?
100ml/ day
How much body water is lost in the skin during prolonged heavy exercise?
350ml / day
How much body water is lost in the skin during prolonged heavy exercise?
350ml / day