Renal localization of albumin and its function in the concentrating mechanism

Fa, Carone; Everett, BA; Blondeel, NJ; Stolarczyk, J

doi:10.1152/ajplegacy.1967.212.2.387

Cited by 27 publications

(7 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In the normal medulla, the hypertonic environment probably causes blood viscosity to rise due to the crenation of red cells (41) and the threefold increase in protein concentration that occurs in the vasa recta (42)(43)(44)(45)(46). Therefore, medullary hypertonicity may determine, in part, the efferent resistance of the juxtamedullary glomneruli.…”

Section: Methodsmentioning

confidence: 99%

A Micropuncture Study of Postobstructive Diuresis in the Rat

Yarger¹,

Aynedjian²,

Bank³

1972

J. Clin. Invest.

100

View full text Add to dashboard Cite

A B S T R A C T In order to investigate the syndrome of postobstructive diuresis, clearance and micropuncture studies were carried out in rats after relief of 24 hr of bilateral (BUL) or unilateral (UUL) ureteral ligation. In rats with BUL, a striking diuresis and natriuresis occurred when the obstruction to one kidney (the experimental kidney) was relieved. The results were not influenced by administration of vasopressin or d-aldosterone. Whole kidney clearances of inulin and p-aminohippuric acid (PAH) in the experimental kidney were reduced to 10% and 20% of normal, respectively. Superficial nephron inulin and PAH clearances were also reduced, but only to 40% and 45%, respectively. These findings suggest a heterogeneity of nephron function in which deep nephrons were functioning poorly or not at all. To investigate the site of impaired tubular reabsorption in the surface nephrons, absolute and fractional water reabsorption was measured. Absolute reabsorption was found to be decreased all along the nephron. Fractional reabsorption in proximal tubules was normal, as indicated *by an average endproximal tubular fluid per plasma inulin (TF/Pi.) of 2.16 vs. 2.30 in controls. TF/Pri was markedly decreased in distal tubules (2.91 vs. 8.02) and final urine (5.56 vs. 263). These observations indicate that the major sites of impaired sodium reabsorption leading to the diuresis were beyond the proximal tubule.

show abstract

Section: Methodsmentioning

confidence: 99%

A Micropuncture Study of Postobstructive Diuresis in the Rat

Yarger¹,

Aynedjian²,

Bank³

1972

J. Clin. Invest.

100

View full text Add to dashboard Cite

show abstract

“…Second, labeled albumin would filter through the glomerular membranes of the kidney to a limited extent and accumulate in the fluid of the nephrons and in tubular cells, thus adding a portion of the tubular fluid volume to the calculated intra vascular volume (22)(23)(24)(25). Third, there is ample evidence that albumin is concentrated in the medulla of the kidney by the countercurrent exchange mechanism, possibly by short circuiting of water across the loop of Henle (26)(27)(28). To the extent that albumin accumulates here it will yield erroneously high values for the calculation of the intravascular plasma volume, thus adding to the total error involved in the measurement of the apparent renal plasma volume (16,18,19,20,29).…”

Section: Selkurt Laurencementioning

confidence: 99%

Examination of the Intrarenal Hematocrit Ratio with the Technique of Circulatory Stop-Flow in Dogs

Selkurt

Laurence

1969

Circulation Research

View full text Add to dashboard Cite

Estimates of the intrarenal hematocrit ratio vary widely, depending on the techniques used for its determination. Computation of blood volume from the product of mean transit time of labeled erythrocytes and albumin, and minute volume blood flow, yields values averaging approximately 90% of the systemic vessel hematocrit. To the other extreme are values that are slightly less than half of the systemic hematocrit ratio based on the determination of total renal blood volume by labeled red cells and albumin. Intermediate values are obtained by methods involving draining the blood from the kidney and measuring its hematocrit ratio. The current investigation, by a technique of circulatory stop-flow, has shown that a substantial fluid shift occurs in the kidney within 2 minutes of circulatory arrest, so that interstitial fluid, supplemented by fluid reabsorbed by the nephrons, dilutes the erythrocytes within the peritubular capillaries to reduce the hematocrit ratio to almost half of the systemic figure. The drainage methods are subject to error as a result of this mechanism, but if such fluid shifts are taken into account, values for the intrarenal hematocrit closer to the ratio of systemic blood can be anticipated.

show abstract

“…Hargitay and Kuhn [10] in their model studies, proposed active transport of sodium in the ascending limb of Henle's loop as the 'Einzeleffekt', and this is the most commonly held view today. Some authors, such as Lever [20] and Carone et al [2] assert that the differ ence in hydrostatic pressure between the descending and ascending limb of the vasa recta is the driving force for the increasing solute concentration in the renal medulla. Pinter andShohet [26] theorized that only the thick, upper portion of the ascending Henle loop is actively pumping sodium.…”

Section: Introductionmentioning

confidence: 99%

A Study of the Renal Countercurrent System by Computer Simulation

Wiener¹

1979

Nephron

View full text Add to dashboard Cite

A model of the renal medulla is formulated, taking into account the transport properties of each medullary structure. Using known data on inflow to the vascular and tubular systems and on urine output in normal man in hydropenia, and assuming medullary osmotic profiles similar to published data on hydropenic dogs, transport coefficients are calculated for each medullary structure. The calculated coefficients compare reasonably well with measurements made in the rat kidney. A normal hydration case is calculated by reducing the collecting duct permeability until a urine output and concentration of 1.0 ml/min and 700 mosm/l is obtained. The coefficients are then kept constant, and medullary osmotic profiles and urine output corresponding to various system inputs are calculated. These studies show that medullary osmolarities decrease and urine flow increases with increasing medullary blood flow and that an optimal rate of proximal reabsorption exists for producing a maximally concentrated urine. Such results are consistent with observations on renal function reported both experimentally and clinically.

show abstract

Renal localization of albumin and its function in the concentrating mechanism

Cited by 27 publications

References 0 publications

A Micropuncture Study of Postobstructive Diuresis in the Rat

A Micropuncture Study of Postobstructive Diuresis in the Rat

Examination of the Intrarenal Hematocrit Ratio with the Technique of Circulatory Stop-Flow in Dogs

A Study of the Renal Countercurrent System by Computer Simulation

Contact Info

Product

Resources

About