Usage Information
Citation Information: J Clin Invest. 1977;60(3):639-647. https://doi.org/10.1172/JCI108815.
Abstract
In vitamin D-deficient rats, impaired intestinal phosphorus (P) absorption can be corrected by 1,25-dihydroxyvitamin D3[1,25-(OH)2D3]. In the present study, it was investigated whether changes in 1,25-(OH)2D3 production can influence intestinal P transport also in animals with a normal supply of vitamin D. The intestinal P absorption was evaluated in rats using both the in situ duodenal loop technique and the determination of the overall gastrointestinal absorption under three conditions known to influence the production of 1,25-(OH)2D3: (a) variation in dietary P, (b) thyroparathyroidectomy (TPTX) with or without administration of parathyroid hormone (PTH), and (c) treatment with disodium ethane-1-hydroxy-1,1-diphosphonate (EHDP). In all circumstances changes in duodenal absorption paralleled the changes in the overall fractional absorption. (a) Lowering dietary P stimulated P absorption. (b) TPTX decreased P absorption. This effect was corrected either by the administration of PTH or by the administration of 1,25-(OH)2D3. (c) EHDP, when given at a dose known to inhibit 1,25-(OH)2D3 formation, decreased the duodenal P absorption in both intact and TPTX animals. This effect was corrected by 1,25-(OH)2D3. In the TPTX-EHDP-treated animals, the administration of PTH did not rectify the low duodenal P absorption. These results support the thesis that, in rats with normal vitamin D supply, variations in the endogenous production of 1,25-(OH)2D3 change the rate of P absorption. However, these changes are in such magnitude that they are of relatively small importance when compared to the effect of variation in the dietary intake of P. These results also strongly suggest that the action of PTH on duodenal P transport is mediated by its effect on 1,25-(OH)2D3 production, inasmuch as the effect of the hormone is abolished after blocking the renal 1-hydroxylation with EHDP.
Authors
R. Rizzoli, H. Fleisch, J-P. Bonjour
Usage data is cumulative from March 2024 through March 2025.
| Usage | JCI | PMC |
|---|---|---|
| Text version | 238 | 8 |
| 74 | 30 | |
| Scanned page | 398 | 2 |
| Citation downloads | 73 | 0 |
| Totals | 783 | 40 |
| Total Views | 823 | |
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.
Copyright © 2025 American Society for Clinical Investigation
ISSN: 0021-9738 (print), 1558-8238 (online)