Abstract:
:The canonical mass balance relation derived for the central core model of the renal medulla is extended to medullary models in which an arbitrary assemblage of renal tubules and vascular capillaries exchange with each other both directly and via the medullary interstitium and in which not all of the vascular loops or loops of Henle extend to the papilla. It is shown that if descending limbs of Henle and descending vasa recta enter the medulla at approximately plasma osmolality, the concentration ratio is given by: r = 1/[1 - ft(1 - fu)(1 - fw)], where ft is fractional solute transport out of ascending Henle's limb, fu is fractional urine flow, and fw is fractional dissipation; fw is a measure of the solute returned to the systemic circulation without its isotonic complement of water. A modified equation that applies to the diluting as well as the concentrating kidney is also derived. By allowing concentrations in interstitium and vascular capillaries to become identical at a given medullary level, conservation relations are derived for a multinephron central core model of the renal medulla.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Stephenson JLdoi
10.1016/S0006-3495(76)85773-6subject
Has Abstractpub_date
1976-11-01 00:00:00pages
1273-86issue
11eissn
0006-3495issn
1542-0086pii
S0006-3495(76)85773-6journal_volume
16pub_type
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