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- Cocicentralion

RENAL PHYSIOLOGY

WATER, ION, AND UREA EXCHANCE IN PRODUCTION OF HYPERTONIC URINE (ADH PRESENT)

Urea

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Na ter V^H₂0 Urca

Notę: Figures given are exemplarv ralher than spccific

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FtGURE 6.10 CONCENTRATION OF THE URINE -

"V excretion of a concentratcd urinc rcquires normaI function of -tt toop ot t lenie (in particular the ihick astemling limb), a hyperos->ik medullary interstitium, the presence of high levels of ADII in no blood. and the normal response of tbc collecling duet to ADH <i.e., inereased water permeability). Under optimal conditions, this result*. in the excretion of 0.5 L/day of urinc having an osmolality of 1200 mOsm/kg 11 O-

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