Skip to main content
PMC home page
The Journal of Clinical Investigation logoLink to The Journal of Clinical Investigation
. 1969 May;48(5):947–956. doi: 10.1172/JCI106054

Effect of hypotonic expansion on sodium, water, and urea excretion in late pregnancy: the influence of posture on these results

Marshall D Lindheimer 1,2, Peter V Weston 1,2
PMCID: PMC322304  PMID: 5780203

Abstract

Mineralocorticoid-treated, normotensive third trimester subjects positioned in lateral recumbency were studied before and during the infusion of 300 mEq of hypotonic saline. Urinary sodium excretion increased in all subjects from a mean value of 199 to 416 μEq/min. In 12 maximally hydrated subjects free water clearance (CH2O) and urine flow (V) increased from means of 7.54 and 9.50 to 11.6 and 14.5 ml/100 ml of glomerular filtrate (GFR) Also the ratio of urea to inulin clearance (Curea/Cinulin) increased from 0.59 to 0.64. The changes in the renal handling of water and urea suggest that fractional sodium reabsorption decreased at proximal nephron sites.

The subjects then assumed a supine position, and the results were compared to those obtained during the lateral recumbent control periods. Filtered sodium decreased in 11 experiments, but in five studies it remained up to 2.6 mEq/min above control values. There was only one instance in which a significant increase in sodium excretion occurred. It was concluded that supine recumbency blunts natriuresis despite volume expansion or an increase in the filtered load of sodium.

Finally, in the 12 hydrated subjects supine recumbency reduced CH2O and V from a mean of 11.6 and 14.5 to 6.2 and 8.2 ml/100 ml of GFR. In eight of these experiments urine osmolality fell or did not change. Simultaneously, Curea/Cinulin fell from 0.64 to 0.57. These data suggest that the antinatriuresis, which occurred when the volume-expanded subjects were positioned in supine recumbency, was accompanied by a decrease in the fractional reabsorption of sodium at proximal nephron sites.

Full text

PDF
954

Selected References

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

  1. BERLINER R. W., DAVIDSON D. G. Production of hypertonic urine in the absence of pituitary antidiuretic hormone. J Clin Invest. 1957 Oct;36(10):1416–1427. doi: 10.1172/JCI103541. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Berliner R. W. Intrarenal mechanisms in the control of sodium excretion. Fed Proc. 1968 Sep-Oct;27(5):1127–1131. [PubMed] [Google Scholar]
  3. CHESLEY L. C., SLOAN D. M. THE EFFECT OF POSTURE ON RENAL FUNCTION IN LATE PREGNANCY. Am J Obstet Gynecol. 1964 Jul 15;89:754–759. doi: 10.1016/0002-9378(64)90178-4. [DOI] [PubMed] [Google Scholar]
  4. CHESLEY L. C., VALENTI C., REIN H. Excretion of sodium loads by nonpregnant and pregnant normal, hypertensive and pre-eclamptic women. Metabolism. 1958 Sep;7(5):575–588. [PubMed] [Google Scholar]
  5. CHESLEY L. C., WYNN R. M., SILVERMAN N. I. RENAL EFFECTS OF ANGIOTENSIN II INFUSIONS IN NORMOTENSIVE PREGNANT AND NONPREGNANT WOMEN. Circ Res. 1963 Sep;13:232–238. doi: 10.1161/01.res.13.3.232. [DOI] [PubMed] [Google Scholar]
  6. Cirksena W. J., Dirks J. H., Berliner R. W. Effect of thoracic cava obstruction on response of proximal tubule sodium reabsorption to saline infusion. J Clin Invest. 1966 Feb;45(2):179–186. doi: 10.1172/JCI105330. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. DE WARDENER H. E., MILLS I. H., CLAPHAM W. F., HAYTER C. J. Studies on the efferent mechanism of the sodium diuresis which follows the administration of intravenous saline in the dog. Clin Sci. 1961 Oct;21:249–258. [PubMed] [Google Scholar]
  8. DIECKMANN W. J., POTTINGER R. E., RYNKIEWICZ L. M. Etiology of preeclampsia-eclampsia. IV. Sodium chloride test for the diagnosis of pre-eclampsia. Am J Obstet Gynecol. 1952 Apr;63(4):783–791. doi: 10.1016/s0002-9378(16)38858-5. [DOI] [PubMed] [Google Scholar]
  9. EARLY L. E., FRIEDLER R. M. OBSERVATIONS ON THE MECHANISM OF DECREASED TUBULAR REABSORPTION OF SODIUM AND WATER DURING SALINE LOADING. J Clin Invest. 1964 Oct;43:1928–1937. doi: 10.1172/JCI105067. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. EPSTEIN F. H., POST R. S., MCDOWELL M. The effects of an arteriovenous fistula on renal hemodynamics and electrolyte excretion. J Clin Invest. 1953 Mar;32(3):233–241. doi: 10.1172/JCI102732. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Earley L. E. Influence of hemodynamic factors on sodium reabsorption. Ann N Y Acad Sci. 1966 Nov 22;139(2):312–327. doi: 10.1111/j.1749-6632.1966.tb41206.x. [DOI] [PubMed] [Google Scholar]
  12. Eknoyan G., Suki W. N., Rector F. C., Jr, Seldin D. W. Functional characteristics of the diluting segment of the dog nephron and the effect of extracellular volume expansion on its reabsorptive capacity. J Clin Invest. 1967 Jul;46(7):1178–1188. doi: 10.1172/JCI105611. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. FARBER S. J., BECKER W. H., EICHNA L. W. Electrolyte and water excretions and renal hemodynamics during induced congestion of the superior and inferior vena cava of man. J Clin Invest. 1953 Nov;32(11):1145–1162. doi: 10.1172/JCI102839. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Gordon R. D., Küchel O., Liddle G. W., Island D. P. Role of the sympathetic nervous system in regulating renin and aldosterone production in man. J Clin Invest. 1967 Apr;46(4):599–605. doi: 10.1172/JCI105561. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. HAYASHI T. T., WILLIAMS J. M., Jr, WILLSON J. R. Hypertonic saline infusions for the differential diagnosis of the toxemias of pregnancy. Am J Obstet Gynecol. 1957 Jan;73(1):30–36. doi: 10.1016/s0002-9378(16)37263-5. [DOI] [PubMed] [Google Scholar]
  16. HECKEL G. P., TOBIN C. E. Arteriovenous shunts in the myometrium. Am J Obstet Gynecol. 1956 Jan;71(1):199–205. doi: 10.1016/0002-9378(56)90695-0. [DOI] [PubMed] [Google Scholar]
  17. Howards S. S., Davis B. B., Knox F. G., Wright F. S., Berliner R. W. Depression of fractional sodium reabsorption by the proximal tubule of the dog without sodium diuresis. J Clin Invest. 1968 Jul;47(7):1561–1572. doi: 10.1172/JCI105848. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. KERR M. G., SCOTT D. B., SAMUEL E. STUDIES OF THE INFERIOR VENA CAVA IN LATE PREGNANCY. Br Med J. 1964 Feb 29;1(5382):532–533. doi: 10.1136/bmj.1.5382.522. [DOI] [PubMed] [Google Scholar]
  19. Katz F. H., Kappas A. The effects of estradiol and estriol on plasma levels of cortisol and thyroid hormone-binding globulins and on aldosterone and cortisol secretion rates in man. J Clin Invest. 1967 Nov;46(11):1768–1777. doi: 10.1172/JCI105667. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. LANDAU R. L., BERGENSTAL D. M., LUGIBIHL K., KASCHT M. E. The metabolic effects of progesterone in man. J Clin Endocrinol Metab. 1955 Oct;15(10):1194–1215. doi: 10.1210/jcem-15-10-1194. [DOI] [PubMed] [Google Scholar]
  21. LANDAU R. L., LUGIBIHL K. Inhibition of the sodium-retaining influence of aldosterone by progesterone. J Clin Endocrinol Metab. 1958 Nov;18(11):1237–1245. doi: 10.1210/jcem-18-11-1237. [DOI] [PubMed] [Google Scholar]
  22. LEVINSKY N. G., LALONE R. C. SODIUM EXCRETION DURING ACUTE SALINE LOADING IN DOGS WITH VENA CAVAL CONSTRICTION. J Clin Invest. 1965 Apr;44:565–573. doi: 10.1172/JCI105169. [DOI] [PMC free article] [PubMed] [Google Scholar]
  23. LEVINSKY N. G., LALONE R. C. THE MECHANISM OF SODIUM DURESIS AFTER SALINE INFUSION IN THE DOG. J Clin Invest. 1963 Aug;42:1261–1276. doi: 10.1172/JCI104811. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Levinsky N. G. Nonaldosterone influences on renal sodium transport. Ann N Y Acad Sci. 1966 Nov 22;139(2):295–303. doi: 10.1111/j.1749-6632.1966.tb41204.x. [DOI] [PubMed] [Google Scholar]
  25. Levitt M. F., Goldstein M. H., Lenz P. R., Wedeen R. Mercurial diuretics. Ann N Y Acad Sci. 1966 Nov 22;139(2):375–387. doi: 10.1111/j.1749-6632.1966.tb41211.x. [DOI] [PubMed] [Google Scholar]
  26. Lichton I. J., Rasa A. P., Hugh J. E. Effects of vasopressin and spironolactone on excretion of water and solutes by the pregnant rat. Am J Physiol. 1968 Jun;214(6):1468–1474. doi: 10.1152/ajplegacy.1968.214.6.1468. [DOI] [PubMed] [Google Scholar]
  27. PRITCHARD J. A., BARNES A. C., BRIGHT R. H. The effect of the supine position on renal function in the near-term pregnant woman. J Clin Invest. 1955 Jun;34(6):777–781. doi: 10.1172/JCI103132. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. RECTOR F. C., Jr, VANGIESEN G., KIIL F., SELDIN D. W. INFLUENCE OF EXPANSION OF EXTRACELLULAR VOLUME ON TUBULAR REABSORPTION OF SODIUM INDEPENDENT OF CHANGES IN GLOMERULAR FILTRATION RATE AND ALDOSTERONE ACTIVITY. J Clin Invest. 1964 Mar;43:341–348. doi: 10.1172/JCI104919. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Rector F. C., Jr, Brunner F. P., Seldin D. W. Mechanism of glomerulotubular balance. I. Effect of aortic constriction and elevated ureteropelvic pressure on glomerular filtration rate, fractional reabsorption, transit time, and tubular size in the proximal tubule of the rat. J Clin Invest. 1966 Apr;45(4):590–602. doi: 10.1172/JCI105373. [DOI] [PMC free article] [PubMed] [Google Scholar]
  30. Rubi R. A., Sala N. L. Ureteral function in pregnant women. 3. Effect of different positions and of fetal delivery upon ureteral tonus. Am J Obstet Gynecol. 1968 May 15;101(2):230–237. [PubMed] [Google Scholar]
  31. SCOTT D. B., KERR M. G. INFERIOR VENA CAVAL PRESSURE IN LATE PREGNANCY. J Obstet Gynaecol Br Commonw. 1963 Dec;70:1044–1049. doi: 10.1111/j.1471-0528.1963.tb15051.x. [DOI] [PubMed] [Google Scholar]
  32. SKEGGS L. T., Jr An automatic method for colorimetric analysis. Am J Clin Pathol. 1957 Sep;28(3):311–322. doi: 10.1093/ajcp/28.3_ts.311. [DOI] [PubMed] [Google Scholar]
  33. STEIN R. M., BERCOVITCH D. D., LEVITT M. F. DUAL EFFECTS OF SALINE LOADING ON RENAL TUBULAR SODIUM REABSORPTION IN THE DOG. Am J Physiol. 1964 Oct;207:826–834. doi: 10.1152/ajplegacy.1964.207.4.826. [DOI] [PubMed] [Google Scholar]
  34. Sarles H. E., Hil S. S., LeBlanc A. L., Smith G. H., Canales C. O., Remmers A. R., Jr Sodium excretion patterns during and following intravenous sodium chloride loads in normal and hypertensive pregnancies. Am J Obstet Gynecol. 1968 Sep 1;102(1):1–7. doi: 10.1016/0002-9378(68)90424-9. [DOI] [PubMed] [Google Scholar]
  35. Segar W. E., Moore W. W. The regulation of antidiuretic hormone release in man: I. Effects of change in position and ambient temperature on blood ADH levels. J Clin Invest. 1968 Sep;47(9):2143–2151. doi: 10.1172/JCI105900. [DOI] [PMC free article] [PubMed] [Google Scholar]
  36. Slatopolsky E., Elkan I. O., Weerts C., Bricker N. S. Studies on the characteristics of the control system governing sodium excretion in uremic man. J Clin Invest. 1968 Mar;47(3):521–530. doi: 10.1172/JCI105748. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Smith H. W., Finkelstein N., Aliminosa L., Crawford B., Graber M. THE RENAL CLEARANCES OF SUBSTITUTED HIPPURIC ACID DERIVATIVES AND OTHER AROMATIC ACIDS IN DOG AND MAN. J Clin Invest. 1945 May;24(3):388–404. doi: 10.1172/JCI101618. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Torres C., Schewitz L. J., Pollak V. E. The effect of small amounts of antidiuretic hormone on sodium and urate excretion in pregnancy. Am J Obstet Gynecol. 1966 Feb 15;94(4):546–558. doi: 10.1016/0002-9378(66)90061-5. [DOI] [PubMed] [Google Scholar]
  39. VANDER A. J., WILDE W. S., MALVIN R. L., SULLIVAN L. P. Re-examination of salt and water retention in congestive heart failure: significance of renal filtration fraction. Am J Med. 1958 Oct;25(4):497–502. doi: 10.1016/0002-9343(58)90039-1. [DOI] [PubMed] [Google Scholar]
  40. WATANABE M., MEEKER C. I., GRAY M. J., SIMS E. A., SOLOMON S. SECRETION RATE OF ALDOSTERONE IN NORMAL PREGNANCY. J Clin Invest. 1963 Oct;42:1619–1631. doi: 10.1172/JCI104847. [DOI] [PMC free article] [PubMed] [Google Scholar]

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

RESOURCES