Journal of the American Society of Nephrology : JASN
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J. Am. Soc. Nephrol. · Dec 2004
Dietary factors and the risk of incident kidney stones in men: new insights after 14 years of follow-up.
Diet plays an important role in the pathogenesis of kidney stones. Because the metabolism of many dietary factors, such as calcium, may change with age, the relation between diet and kidney stones may be different in older adults. Uncertainty also remains about the association between many dietary factors, such as vitamin C, magnesium, and animal protein, and the risk of kidney stone formation. ⋯ In conclusion, the association between calcium intake and kidney stone formation varies with age. Magnesium intake decreases and total vitamin C intake seems to increase the risk of symptomatic nephrolithiasis. Because age and body size affect the relation between diet and kidney stones, dietary recommendations for stone prevention should be tailored to the individual patient.
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J. Am. Soc. Nephrol. · Dec 2004
Regulation of the Cl-/HCO3- exchanger AE2 in rat thick ascending limb of Henle's loop in response to changes in acid-base and sodium balance.
The Cl(-)/HCO(3)(-) exchanger AE2 is believed to be involved in transcellular bicarbonate reabsorption that occurs in the thick ascending limb of Henle's loop (TAL). The purpose of this study was to test whether chronic changes in acid-base status and sodium intake regulate AE2 polypeptide abundance in the TAL of the rat. Rats were subjected to 6 d of loading with NaCl, NH(4)Cl, NaHCO(3), KCl, or KHCO(3). ⋯ In contrast, NH(4)Cl loading increased AE2 abundance only in the cortical TAL but not in the medullary TAL. These results suggest that regulation of the basolateral Cl(-)/HCO(3)(-) exchanger AE2 plays an important role in the adaptation of bicarbonate absorption in the TAL during chronic acid-base disturbances and high sodium intake. The present study also emphasizes the contribution of cortical TAL adaptation in the renal regulation of acid-base status.