Abstract
Cortical thick ascending limbs of Henle's loop were dissected from the kidneys of chronically vitamin D-deficient or -replete rabbits and perfused in vitro. Unidirectional transepithelial calcium fluxes from lumen to bath were measured with 45Ca. The tubules were bathed in a solution containing 150 mM sodium and perfused with a solution containing 60 mM sodium to simulate conditions in the cortical thick ascending limb in vivo. Transepithelial voltages were equal across tubules from vitamin D-deficient and -replete rabbits. Likewise, baseline and parathyroid hormone-stimulated calcium fluxes were the same in tubules from the two groups. Because calcidiol and calcitriol were undetectable in the serum of the vitamin D-deficient rabbits, we suggest that neither of these endogenous vitamin D metabolites is essential in the regulation of calcium absorption in this portion of the rabbit nephron.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 913-917 |
| Number of pages | 5 |
| Journal | Kidney international |
| Volume | 31 |
| Issue number | 4 |
| DOIs | |
| State | Published - 1987 |
Funding
This study was supported in part by grants AM35985 (JEB) and AM36821 (CBL) from the National Institutes of Health and by grant pelijk Onderzoek." This work was done during the tenure of an Established Investigatorship from the American Heart Association and with funds contributed in part by the Chicago Heart Association (JEB). We thank Laura McNeill, Neil Knutsen, and W. Coopmans for tech- nical assistance and Lorraine Butler for secretarial assistance.
ASJC Scopus subject areas
- Nephrology