{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,2,7]],"date-time":"2024-02-07T17:56:26Z","timestamp":1707328586961},"reference-count":0,"publisher":"Canadian Science Publishing","issue":"10","license":[{"start":{"date-parts":[[1985,10,1]],"date-time":"1985-10-01T00:00:00Z","timestamp":496972800000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/www.nrcresearchpress.com\/page\/about\/CorporateTextAndDataMining"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Can. J. Physiol. Pharmacol."],"published-print":{"date-parts":[[1985,10,1]]},"abstract":"<jats:p> To investigate the possible role of a Na transport defect in the pathogenesis of the phosphaturia in vitamin D resistant rickets, we studied the activity of the Na\u2013K ATPase activity along the microdissected segments of the nephron in normal (N) and hypophosphatemic mice (Hyp), the Na uptake by renal brush border membrane (BBM), as well as the interrelationship between Na and phosphate transport through this membrane. In N mice, Na-K ATPase activity was present in decreasing order, in the distal tubule, the ascending branch of the loop of Henle, the proximal tubule, and the collecting tubule. In Hyp mice, the Na\u2013K ATPase activity was comparable to that measured in N mice, except in the granular segment of the distal tubule where a 256% of the control activity was reproducibly observed. In N mice, Na initial uptake by BBM vesicles increased with Na concentration in the incubation medium, according to two kinetic components: one saturable, evident at low substrate concentrations and the other, nonsaturable, corresponding to a passive diffusion. The addition of 5\u2002mM PO<jats:sub>4<\/jats:sub> in the incubation medium did not significantly influence Na transport. In contrast, Na concentration in the incubation medium largely modified the kinetics of PO<jats:sub>4<\/jats:sub> uptake: increasing Na concentration enhanced PO<jats:sub>4<\/jats:sub> uptake and decreased the apparent K<jats:sub>m<\/jats:sub>. In Hyp mice, Na uptake by BBM was identical to that observed in N mice, but PO<jats:sub>4<\/jats:sub> uptake was decreased by half. Na concentration in the incubation medium similarly influenced PO<jats:sub>4<\/jats:sub> uptake in N and Hyp mice, and the K<jats:sub>m<\/jats:sub> values at each concentration of Na were comparable in the two series of animals. It is concluded that the defect in PO<jats:sub>4<\/jats:sub> transport in Hyp mice is not secondary to an alteration of Na transport through the BBM, nor to an abnormal relationship between Na and PO<jats:sub>4<\/jats:sub> in the PO<jats:sub>4<\/jats:sub> carrier system, nor to a decreased Na\u2013K ATPase activity in the basolateral membrane of the cell. The increase in Na\u2013K ATPase in the distal tubule is probably a secondary phenomenon, not directly related to the pathogenesis of the disease. <\/jats:p>","DOI":"10.1139\/y85-221","type":"journal-article","created":{"date-parts":[[2011,4,24]],"date-time":"2011-04-24T04:53:40Z","timestamp":1303620820000},"page":"1339-1344","source":"Crossref","is-referenced-by-count":5,"title":["Renal sodium transport in vitamin D resistant hypophosphatemic rickets"],"prefix":"10.1139","volume":"63","author":[{"given":"Mich\u00e8le G.","family":"Brunette","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ghazi El","family":"Mernissi","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Alain","family":"Doucet","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"155","container-title":["Canadian Journal of Physiology and Pharmacology"],"original-title":[],"language":"en","link":[{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/pdf\/10.1139\/y85-221","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2020,1,5]],"date-time":"2020-01-05T11:22:17Z","timestamp":1578223337000},"score":1,"resource":{"primary":{"URL":"http:\/\/www.nrcresearchpress.com\/doi\/10.1139\/y85-221"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[1985,10,1]]},"references-count":0,"journal-issue":{"issue":"10","published-print":{"date-parts":[[1985,10,1]]}},"alternative-id":["10.1139\/y85-221"],"URL":"https:\/\/doi.org\/10.1139\/y85-221","relation":{},"ISSN":["0008-4212","1205-7541"],"issn-type":[{"value":"0008-4212","type":"print"},{"value":"1205-7541","type":"electronic"}],"subject":[],"published":{"date-parts":[[1985,10,1]]}}}