Skip to main content
PMC home page
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1985 Aug;76(2):561–566. doi: 10.1172/JCI112007

In vivo and in vitro studies of urinary concentrating ability in potassium-depleted rabbits.

K H Raymond, K K Davidson, T D McKinney
PMCID: PMC423861  PMID: 2993361

Abstract

The factors responsible for the urinary concentrating defect associated with the potassium-depleted (KD) state are uncertain. The present studies were designed to, first, determine whether a urinary concentrating defect exists in potassium-depleted rabbits and, second, to use the technique of in vitro perfusion to evaluate directly the antidiuretic hormone (ADH) responsiveness of cortical collecting tubules (CCT) in this setting. Feeding female New Zealand White rabbits a potassium-deficient diet for 2 wk caused a significant fall in plasma potassium levels in both the ad-libitum and controlled water intake groups (P less than 0.001). Muscle potassium content after 2 wk of potassium restriction fell from 45.6 +/- 0.9 to 29.0 +/- 1.2 meq/100 g fat-free dry solids (P less than 0.001). Renal papillary sodium content fell significantly from a control value of 234.6 +/- 8.0 to 182.46 +/- 10.0 meq/kg H2O after 2 wk of potassium restriction. Maximal urinary osmolality measured after 12 h of dehydration and 1.25 U pitressin IM was significantly decreased in rabbits after 2 wk of potassium restriction in both the ad-libitum and controlled water intake groups (P less than 0.001). The relationship between plasma potassium concentration and maximum urinary osmolality was significantly correlated in both the ad-libitum and controlled water intake groups, r = 0.73 and 0.68 (P less than 0.001), respectively. In addition, refeeding KD rabbits with normal chow for 1 wk resulted in normalization of both plasma potassium levels and urinary concentrating ability. CCT from control and KD rabbits were perfused in vitro at 25 degrees C. The hydraulic conductivity coefficient, Lp, was significantly reduced at all doses of ADH tested in tubules from KD rabbits when compared with control tubules. In addition, the maximal hydraulic conductivity in tubules from KD rabbits when tested with 200 microU/ml ADH at 37.5 degrees C was only 23% of control values (P less than 0.05). Furthermore, this reduced ADH responsiveness persisted when the bath potassium was elevated from 5 to 20 mM. The reflection coefficient for NaCl when compared with raffinose was 0.91 in tubules from KD animals. Thus, these data suggest that the ADH-resistant urinary concentrating defect associated with potassium depletion is due, at least in part, to a diminished responsiveness of the CCT to ADH. Therefore, further studies were designed to investigate the cellular steps involved in this abnormal response. There was no difference in the 8-para-chlorophenylthio cyclic AMP induced hydroosmotic response between CCT from KD and control rabbits. Since the cAMP-induced hydroosmotic response was similar between KD and control CCT, experiments were performed to evaluate the contribution of phosphodiesterase (PDIE) activity by using the potent PDIE inhibitor isobutylmethylxanthine (10(-4) and 10(-3)M) in the presence of ADH (200 U/ml). Although Lp was increased by PDIE inhibition in CCT from both control and KD animals, the overall hydroosmotic response in CCT from KD rabbits was still significantly reduced when compared with controls. The final experiments used forskolin to evaluate further the adenylate cyclase complex. The resulting hydroosmotic response in CCT from KD rabbits was almost identical to that obtained in controls. In conclusion, these data suggest that the decreased responsiveness of CCT from KD rabbits to ADH involves a step at or proximal to the stimulation of the catalytic subunit of adenylate cyclase, and that PDIE activity makes no contribution to this abnormal hydroosmotic response.

Full text

PDF
561

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Beck N., Webster S. K. Impaired urinary concentrating ability and cyclic AMP in K+-depleted rat kidney. Am J Physiol. 1976 Oct;231(4):1204–1208. doi: 10.1152/ajplegacy.1976.231.4.1204. [DOI] [PubMed] [Google Scholar]
  2. Berl T., Linas S. L., Aisenbrey G. A., Anderson R. J. On the mechanism of polyuria in potassium depletion. The role of polydipsia. J Clin Invest. 1977 Sep;60(3):620–625. doi: 10.1172/JCI108813. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Burg M., Grantham J., Abramow M., Orloff J. Preparation and study of fragments of single rabbit nephrons. Am J Physiol. 1966 Jun;210(6):1293–1298. doi: 10.1152/ajplegacy.1966.210.6.1293. [DOI] [PubMed] [Google Scholar]
  4. Carney S., Rayson B., Morgan T. A study in vitro of the concentrating defect associated with hypokalaemia and hypercalcaemia. Pflugers Arch. 1976 Oct 15;366(1):11–17. [PubMed] [Google Scholar]
  5. Du Bois R., Vernoiry A., Abramow M. Computation of the osmotic water permeability of perfused tubule segments. Kidney Int. 1976 Dec;10(6):478–479. doi: 10.1038/ki.1976.135. [DOI] [PubMed] [Google Scholar]
  6. Finn A. L., Handler J. S., Orloff J. Relation between toad bladder potassium content and permeability response to vasopressin. Am J Physiol. 1966 Jun;210(6):1279–1284. doi: 10.1152/ajplegacy.1966.210.6.1279. [DOI] [PubMed] [Google Scholar]
  7. Grantham J. J., Burg M. B. Effect of vasopressin and cyclic AMP on permeability of isolated collecting tubules. Am J Physiol. 1966 Jul;211(1):255–259. doi: 10.1152/ajplegacy.1966.211.1.255. [DOI] [PubMed] [Google Scholar]
  8. Grantham J. J., Orloff J. Effect of prostaglandin E1 on the permeability response of the isolated collecting tubule to vasopressin, adenosine 3',5'-monophosphate, and theophylline. J Clin Invest. 1968 May;47(5):1154–1161. doi: 10.1172/JCI105804. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Gutsche H. U., Peterson L. N., Levine D. Z. In vivo evidence of impaired solute transport by the thick ascending limb in potassium-depleted rats. J Clin Invest. 1984 Apr;73(4):908–916. doi: 10.1172/JCI111314. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. HOLLANDER W., Jr, WINTERS R. W., WILLIAMS T. F., BRADLEY J., OLIVER J., WELT L. G. Defect in the renal tubular reabsorption of water associated with potassium depletion in rats. Am J Physiol. 1957 Jun;189(3):557–563. doi: 10.1152/ajplegacy.1957.189.3.557. [DOI] [PubMed] [Google Scholar]
  11. Hall D. A., Barnes L. D., Dousa T. P. Cyclic AMP in action of antidiuretic hormone: effects of exogenous cyclic AMP and its new analogue. Am J Physiol. 1977 Apr;232(4):F368–F376. doi: 10.1152/ajprenal.1977.232.4.F368. [DOI] [PubMed] [Google Scholar]
  12. KLEEMAN C. R., MAXWELL M. H. Contributory role of extrarenal factors in the polyuria of potassium depletion. N Engl J Med. 1959 Feb 5;260(6):268–271. doi: 10.1056/NEJM195902052600604. [DOI] [PubMed] [Google Scholar]
  13. Kannegiesser H., Lee J. B. Role of outer renal medullary metabolism in the concentrating defect of K depletion. Am J Physiol. 1971 Jun;220(6):1701–1707. doi: 10.1152/ajplegacy.1971.220.6.1701. [DOI] [PubMed] [Google Scholar]
  14. Kim J. K., Jackson B. A., Edwards R. M., Dousa T. P. Effect of potassium depletion on the vasopressin-sensitive cyclic AMP system in rat outer medullary tubules. J Lab Clin Med. 1982 Jan;99(1):29–38. [PubMed] [Google Scholar]
  15. Kim J. K., Summer S. N., Berl T. The cyclic AMP system in the inner medullary collecting duct of the potassium-depleted rat. Kidney Int. 1984 Oct;26(4):384–391. doi: 10.1038/ki.1984.186. [DOI] [PubMed] [Google Scholar]
  16. Kirschenbaum M. A., Lowe A. G., Trizna W., Fine L. G. Regulation of vasopressin action by prostaglandins. Evidence for prostaglandin synthesis in the rabbit cortical collecting tubule. J Clin Invest. 1982 Dec;70(6):1193–1204. doi: 10.1172/JCI110718. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Knepper M., Burg M. Organization of nephron function. Am J Physiol. 1983 Jun;244(6):F579–F589. doi: 10.1152/ajprenal.1983.244.6.F579. [DOI] [PubMed] [Google Scholar]
  18. Kokko J. P., Rector F. C., Jr Countercurrent multiplication system without active transport in inner medulla. Kidney Int. 1972 Oct;2(4):214–223. doi: 10.1038/ki.1972.97. [DOI] [PubMed] [Google Scholar]
  19. Luke R. G., Wright F. S., Fowler N., Kashgarian M., Giebisch G. H. Effects of potassium depletion on renal tubular chloride transport in the rat. Kidney Int. 1978 Nov;14(5):414–427. doi: 10.1038/ki.1978.146. [DOI] [PubMed] [Google Scholar]
  20. MANITIUS A., LEVITIN H., BECK D., EPSTEIN F. H. On the mechanism of impairment of renal concentrating ability in potassium deficiency. J Clin Invest. 1960 Apr;39:684–692. doi: 10.1172/JCI104084. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. McKinney T. D., Burg M. B. Bicarbonate absorption by rabbit cortical collecting tubules in vitro. Am J Physiol. 1978 Feb;234(2):F141–F145. doi: 10.1152/ajprenal.1978.234.2.F141. [DOI] [PubMed] [Google Scholar]
  22. McKinney T. D., Myers P. Bicarbonate transport by proximal tubules: effect of parathyroid hormone and dibutyryl cyclic AMP. Am J Physiol. 1980 Mar;238(3):F166–F174. doi: 10.1152/ajprenal.1980.238.3.F166. [DOI] [PubMed] [Google Scholar]
  23. RUBINI M. E. Water excrtion in potassium-deficient man. J Clin Invest. 1961 Dec;40:2215–2224. doi: 10.1172/JCI104448. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Rutecki G. W., Cox J. W., Robertson G. W., Francisco L. L., Ferris T. F. Urinary concentrating ability and antidiuretic hormone responsiveness in the potassium-depleted dog. J Lab Clin Med. 1982 Jul;100(1):53–60. [PubMed] [Google Scholar]
  25. Schafer J. A., Andreoli T. E. The effect of antidiuretic hormone on solute flows in mammalian collecting tubules. J Clin Invest. 1972 May;51(5):1279–1286. doi: 10.1172/JCI106922. [DOI] [PMC free article] [PubMed] [Google Scholar]
  26. Schwartz M. J., Kokko J. P. Urinary concentrating defect of adrenal insufficiency. Permissive role of adrenal steroids on the hydroosmotic response across the rabbit cortical collecting tubule. J Clin Invest. 1980 Aug;66(2):234–242. doi: 10.1172/JCI109849. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Seamon K., Daly J. W. Activation of adenylate cyclase by the diterpene forskolin does not require the guanine nucleotide regulatory protein. J Biol Chem. 1981 Oct 10;256(19):9799–9801. [PubMed] [Google Scholar]
  28. Stephenson J. L. Concentration of urine in a central core model of the renal counterflow system. Kidney Int. 1972 Aug;2(2):85–94. doi: 10.1038/ki.1972.75. [DOI] [PubMed] [Google Scholar]
  29. Toback F. G., Ordónez N. G., Bortz S. L., Spargo B. H. Zonal changes in renal structure and phospholipid metabolism in potassium-deficient rats. Lab Invest. 1976 Feb;34(2):115–124. [PubMed] [Google Scholar]

Articles from Journal of Clinical Investigation are provided here courtesy of American Society for Clinical Investigation

RESOURCES