Kidney Function And Disease Flashcards
Explain the reabsorptive function of the kidney.
Passive/active movement of water and dissolved substances from the fluid inside the tubule through the tubule wall into the space outside. Water and substances move through the capilliary walls back into your bloodstream. Sodium bicarbonate and sodium chloride are reabsorbed in the proximal tubule. The amount of sodium influences blood volume and pressure.
What is the endocrine function of the kidney?
Water absorption is controlled by vasopressin. Na reabsorption from tubular fluid and K and H transport into tubular fluid is controlled by aldosterone.
What is the function of the glomerulus and tubule?
Glomerulus filters your blood. The tubule returns needed substances to your blood and removes wastes.
What is the GFR and its significance?
Glomerular filtration rate is a chief measure of kidney function. It represents the flow of plasma from the glomerulus into the Bowman’s space over a specified period. Approx. 180L per day.
How is drug clearance affected by GFR?
NSAIDs and ACE inhibitors decrease GFR. Angiotensin II normally constricts the efferent arteriole. ACE inhibitors will dilate the efferent arteriole.
What is the regulatory function of the kidney? (In terms of blood pressure)
Kidney effects Na+ and water balance, which determines blood pressure. The 2 sensors are low Na+/low perfusion pressure. This stimulates renin release which cleaves angiotensinogen to generate angiotensin I. Angiotensin I is converted to Angiotensin II, which triggers vasoconstriction and raises blood pressure. It also stimulates aldosterone production and secretion resulting in Na+ and H2O retention in the collecting duct. ECF increases, alleviates renin release.
What is the relationship between vasopressin and aldosterone and the kidneys?
Low levels will cause the kidneys to excrete too much water, leading to dehydration and a fall in blood pressure.
What the homeostasis mechanism of acid/base balance?
When pH decreases, H+ concentration increases. This increases CO2, which is exhaled. This decreases the body’s bicarbonate, the kidneys then excrete additional H, restoring bicarbonate levels.
What about Ca metabolism?
Site of 24-hydroxylation of 25 hydroxycholecalciferol. This produces calcitriol. Increases Ca+2 absorption from the gut.
What is kidney disease and what are some things that can cause kidney disease?
Any disease, disorder or condition that affects the kidney. NSAIDs can cause renal failure, as prostaglandins are powerful, locally-acting vasodilators.
Angiotensin II-mediated vasoconstriction helps patients with renal hypoperfusion.
What is blood urea nitrogen?
Its a test that measures the amount of nitrogen in your blood that comes from urea. Urea nitrogen is created in the liver when the body breaks down proteins. BUN levels are elevated when the kidneys or liver are damaged.
List 4 medications that can elevate BUN levels.
Carbamazepine, furosemide, methyldopa, rifampicin, spironolactone, tetracycline, vancomycin.
