Kokko and Rector Model

The Kokko and Rector model is a theory explaining the mechanism of generation of a gradient in the inner medulla of the kidney. Unlike earlier theories explaining the mechanism using counter current mechanism (as is the case in the outer medulla), the driving force for salt reabsorption is stated to be urea accumulation. It has been proved that counter current mechanism cannot be the case in the inner medulla, since there are no salt pumps, and the cell membrane is too permeable to salt.

History

It has been proposed by JP Kokko and FC Rector Jr in 1972.

Further reading

• Vasopressin. John Libbey Eurotext. 1993. pp. 408–. ISBN 978-2-7420-0031-9.
• Britton, KE; Cage, PE; Carson, ER (May 1976). "A 'bootstrap' model of the renal medulla". Postgrad Med J. 52 (607): 279–284. doi:10.1136/pgmj.52.607.279. PMC 2496524. PMID 959103.
• Pruitt, M. E. C.; Knepper, MA; Graves, B; Schmidt-Nielsen, B (2005). "Effect of peristaltic contractions of the renal pelvic wall on solute concentrations of the renal inner medulla in the hamster". AJP: Renal Physiology. 290 (4): F892–6. doi:10.1152/ajprenal.00323.2005. PMC 1400599. PMID 16234309.