First Aid - Renal Physiology IV Flashcards
What are the five primary hormones that act on the kidneys?
Angiotensin II (AT II), Atrial Natriuretic Peptide (ANP), Parathyroid Hormone (PTH), Aldosterone, Antidiuretic Hormone (ADH/Vasopressin)
What are the actions and net effect of AT II on the kidney?
AT is synthesized in response to low BP. AT II constricts the efferent arteriole, increasing GFR and FF, and stimulates Na+ reabsorption. Preserves renal function in low volume states by increasing FF and maintains circulating volume through increased Na+ reabsorption.
What are the actions and net effect of ANP on the kidney?
ANP is secreted by the atria in response to increased atrial pressure. It causes increased GFR and Na+ filtration with no compensatory Na+ reabsorption. This leads to Na+ and volume loss.
What are the actions and net effect of Parathyroid hormone on the kidney?
PTH is secreted in response to low plasma [Ca2+], high plasma [PO4-], or low plasma 1,25-Vit D. Causes inc Ca2+ reabsorption, dec PO4 reabsorption, and increased 1,25-Vit D production.
What are the actions and net effects of Aldosterone in the kidney?
Aldosterone is secreted in response to decrease blood volume (by adrenal gland, via AT II) and increased plasma [K+]. Causes inc Na+ reabsorption, inc K+ secretion, and inc H+ secretion.
What are the actions and net effect of ADH in the kidney?
ADH (Vasopressin) is secreted in response to inc plasma osmolarity and dec blood volume. Binds to receptors on Principle cells causing inc # of aquaporins and inc H2O reabsorption.
Possible causes of hyperkalemia (K+ shifting out of cells)
“DO Insulin LAB” - Digitalis, HyperOsmolarity, Insulin deficiency, Lysis of cells, Acidosis, B-adrenergic antagonist
Possible causes of hypokalemia (K+ shifting into cells)
“INsulin shifts K+ INto cells” - Hypo-osmolarity, Insulin, Alkalosis, B-adrenegic agonist
Symptoms of high and low serum Na+
Low: Nausea, malaise, stupor, coma; High: Irritability, stupor, coma
Symptoms of high and low serum K+
Low: U-waves on ECG, flattened T-waves, arrhythmias, muscle weakness; High: Wide QRS and peaked T-waves, arrhythmias, muscle weakness.
Symptoms of high and low serum Ca2+
Low: Tetany, seizures, QT prolongation; High: Stones (renal), bones (pain), groans (abdominal pain), psychiatric overtones (anxiety, altered mental status), not necessarily calciuria.
Symptoms of high and low Mg2+
Low: Tetany, torsades de pointes; High: Dec DTRs, lethargy, bradycardia, hypotension, cardiac arrest, hypocalcemia
Symptoms of high and low PO4-
Low: Bone loss, osteomalacia; High: Renal stones, metastatic calcifications, hypocalcemia
What is the cause and compensation for metabolic acidosis?
Metabolic acidosis is caused by decreased [HCO3-], compensation is by immediate hyperventilation (dec CO2.
What is the cause and compensation for metabolic alkalosis?
Metabolic alkalosis is caused by increased [HCO3-], compensation is immediate hypoventilation (inc CO2).
