Chapter 19 - Alterations in Hormonal Regulation Flashcards
Abnormal secretion of ADH is a disorder of the ___________ gland
posterior pituitary
ADH is aka ___________
vasopressin, hormone that signals water reabsorption
Reduced ADH secretion leads to water __________ and ECF ____________
secretion; hyperosmolarity
Excess ADH secretion leads to water ________ and ECF _____________
reabsorption; hypo-osmolarity
Disease of the posterior pituitary can also lead to insufficient hormonal _______ proteins in plasma
carrier
What does SIADH stand for?
syndrome of inappropriate (EXCESSIVE) antidiuretic hormone
When does SIADH occur?
when high ADH levels are present in the absence of normal stimuli for its release
SIADH can be caused by: (3)
-ectopic ADH secretion via tumour
-surgery
-medications
Cancers of the _______, duodenum, and ______ as well as lymphomas and sarcomas can lead to SIADH
stomach; pancreas
SIADH can be caused by CNS disorders such as: (2)
encephalitis and meningitis
Surgery can result in increased ADH for __-__ days
5-7
Why does surgery lead to SIADH?
fluid and volume changes occur after surgery
How is ADH released following pituitary surgery?
unregulated
____________ medications for diabetes mellitus, along with opioids, antidepressants, and anti___________ may lead to SIADH
Hypo-glycemic; inflammatories
SIADH’s key feature is increased water ________ by the kidneys to the peritubular capillaries
reabsorption
Increased ADH secretion leads to an increase in which protein being inserted into the luminal membrane?
water channel proteins
Na+ = H20 is _______ osmolarity
normal
more Na+ than H20 = _____osmolarity
hyper
less Na+ than H2- = ______-osmolarity
hypo
Hyponatremia causes the symptoms of _______-
SIADH
Hyponatremia occurs when _____ in the blood is low
Na+
The effects of SIADH depend on how fast and ________ onset is
severe
What is a normal serum sodium level?
140-130 mmol/L
What serum sodium level signifies vomiting, abdominal cramps, and weight gain?
130-120 mmol/L
What serum sodium level involves confusion, lethargy, muscle twitches, and convulsions?
below 110 mmol/L
Correction of hyponatremia…
resolves symptoms
Diabetes insipidus is an ______ insufficiency
ADH
DI leads to polyuria and poly______
polydipsia
Polyuria
frequent urination
Polydipsia
frequent drinking
DI can be _______ (central) or nephrogenic
neurogenic
Neurogenic DI is caused by: insufficient ____ secretion, lesions on the ________, interference with ADH transport/________, brain tumours, aneurysms, TBI
ADH; hypothalamus; release
Nephrogenic DI can be ________ or genetic
acquired
Acquired DI is related to medication disorders that damage ______ ______
renal tubules
What are the two disorders that cause acquired DI?
-pyelonephritis
-polycystic kidney disease
Pyelonephritis
urinary tract infection
Polycystic Kidney Disease
genetic disorder that causes many fluid-filled cysts to grow in your kidneys
Genetic DI occurs from a mutation of the gene coding for _________-__
aquaporon-2 (water channel)
DI associated with pregnancy is ______
rare
Gestational DI involves an increase in ____________
vasopressinase (vasopressin-degrading enzyme)
Gestational DI is usually ______ and doesn’t require treatment
mild
DI leads to a large volume of ________ urine
dilute
DI _________ plasma osmolarity
increases
What are the clinical signs of DI?
-polyuria
-nocturia (waking at night to pee)
-polydipsia
What is a normal urinary output?
1-2 L/day
DI can cause urine output to be as high as __-___ L/day (may be higher than daily fluid intake!)
8-12
Longstanding DI leads to an enlarged _______ _______ and hydronephrosis
bladder capacity
Hydronephrosis
swelling of one or both kidneys
Neurogenic DI has a _______ onset
sudden
Nephrogenic DI has a ________ onset
gradual
How is DI diagnosed?
-dilute urine
-hyperosmolarity
-hypernatremia
Continued diuresis despite high serum osmolarity is abnormal because normally there is only extra urine when….
the body needs to get rid of something