The mechanism of sodium retention by the kidney in rats with ligation of the common bile duct was studied with micropuncture techniques. 10-14 days after bile duct ligation, rats showed positive sodium balance and ascites formation. Measurements of renal blood flow and glomerular filtration rate yielded values that were not different from those in normal control animals. Likewise, single nephron filtration rte of surface nephrons was the same in the experimental rats as in the controls. Sodium reabsorption, however, was markedly increased in the proximal convoluted tubule, as well as in segments beyond the proximal convolutions. Single nephron filtration fraction, calculated from measurements of efferent arteriolar and arterial hematocrits, was significantly elevated in the cortical nephrons, even though whole kidney filtration fraction was the same as in normal rats. The calculated protein concentration of cortical peritubular blood was higher in the bile duct-ligated rats than in the normal controls. The observations are consistent with the view that sodium retention is the result of enhanced reabsorption primarily by cortical nephrons. The enhanced reabsorption can be accounted for by relative cortical ischemia due to efferent arteriolar vasoconstriction with the consequent elevation of peritubular colloid oncotic pressure.
N Bank, H S Aynedjian
Usage data is cumulative from April 2023 through April 2024.
Usage | JCI | PMC |
---|---|---|
Text version | 71 | 0 |
37 | 20 | |
Scanned page | 86 | 2 |
Citation downloads | 4 | 0 |
Totals | 198 | 22 |
Total Views | 220 |
Usage information is collected from two different sources: this site (JCI) and Pubmed Central (PMC). JCI information (compiled daily) shows human readership based on methods we employ to screen out robotic usage. PMC information (aggregated monthly) is also similarly screened of robotic usage.
Various methods are used to distinguish robotic usage. For example, Google automatically scans articles to add to its search index and identifies itself as robotic; other services might not clearly identify themselves as robotic, or they are new or unknown as robotic. Because this activity can be misinterpreted as human readership, data may be re-processed periodically to reflect an improved understanding of robotic activity. Because of these factors, readers should consider usage information illustrative but subject to change.