drink large volumes of water produce large volume of hypotonic urine

Drink large volumes of water produce large volume of

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drink large volumes of water, produce large volume of hypotonic urine Dehydration causes low urine output of hypertonic urine
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Hormones Affecting Renal Function Hormones Affecting Renal Function Aldosterone – promotes Na + reabsorption and K + secretion, reduces urine output ADH – promotes water reabsorption, reduces urine output Angiotensin II – constricts vessels BP, promotes water reabsorption, stimulates aldosterone and ADH secretion ANP – inhibits NaCl and water reabsorption, dilates afferent and constrict efferent vessels, increases urine output Calcitonin/Calcitriol – promotes Ca 2+ reabsorption weakly Epinephrine/Norepinephrine – induces renin secretion and constricts afferent arteriole, reduces urine output PTH – promotes Ca 2+ reabsorption
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3 Factors Affect Blood Pressure 3 Factors Affect Blood Pressure 1. Heart Rate NE binds beta-adrenergic receptor ↑heart rate ↑BP Hypertension treated with beta-blocker 2. Vessel Diameter Renin ACE Angiotenisin II vasoconstriction ↑BP Hypertension treated with renin inhibitor, ACE inhibitor, or angiotensin II receptor blocker 3. Blood Volume ↑ Na + ↑ blood volume ↑BP Hypertension treated with diuretics like Lasix Na + pump inhibitor
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Urinalysis – Urine Composition
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Urine Volume Normal volume - 1 to 2 L/day Polyuria > 2L/day Oliguria < 500 mL/day Anuria - 0 to 100 mL/day
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Diabetes Chronic polyuria of metabolic origin With hyperglycemia and glycosuria diabetes mellitus I and II , insulin hyposecretion/insensitivity gestational diabetes , 1 to 3% of pregnancies ADH hyposecretion diabetes insipidus ; CD water reabsorption
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Diuretics Effects urine output blood volume Uses hypertension and congestive heart failure Mechanisms of action GFR – high doses of caffeine tubular reabsorption alcohol (inhibits ADH) Lasix “loop diuretic” inhibit Na + , K + , Cl - thick segment
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Renal Function Tests Renal clearance : volume of plasma cleared of a waste in 1 minute Determine renal clearance (C) by assessing blood and urine samples: C = UV/P U (waste concentration in urine) V (rate of urine output) P (waste concentration in plasma) Determine GFR: inulin is neither reabsorbed or secreted so its GFR = renal clearance GFR = UV/P Clinical GFR estimated from creatinine excretion
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Urine Storage and Elimination Ureters ( about 25 cm long) 3 layers adventitia - CT muscularis - 2 layers of smooth muscle urine enters, it stretches and contracts in peristaltic wave mucosa - transitional epithelium lumen very narrow, easily obstructed renal calculi (kidney stones) Lithotripsy – ablation of stones
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Renal Calculi
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Urinary Bladder 3 layers parietal peritoneum , superiorly; fibrous adventitia rest muscularis : detrusor muscle, 3 layers of smooth muscle mucosa : transitional epithelium trigone : openings of ureters and urethra, triangular rugae : relaxed bladder wrinkled, highly distensible capacity: moderately full - 500 ml, max. - 800 ml
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  • Spring '15
  • lamb
  • Physiology, Anatomy, Nephron loop, afferent arteriole, urine output

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