Effect of calcium on oxalate uptake and transport by the rat intestine

Intestinal transport of an obdurate anion: oxalate

In this review, we focus on the role of gastrointestinal transport of oxalate primarily from a contemporary physiological standpoint with an emphasis on those aspects that we believe may be most important in efforts to mitigate the untoward effects of oxalate. Included in this review is a general discussion of intestinal solute transport as it relates to oxalate, considering cellular and paracellular avenues, the transport mechanisms, and the molecular identities of oxalate transporters. In addition, we review the role of the intestine in oxalate disease states and various factors affecting oxalate absorption.

Sodium chloride-dependent oxalate absorption in the human gut

We investigated the effect of sodium chloride intake on oxalate and calcium metabolism in the human body. In healthy subjects with a simultaneous intake of sodium oxalate (4 μmoles/kg body weight) and sodium chloride (1.2 mmoles/kg body weight), the change in oxalate-creatinine ratio was 2.04 ± 0.74, and 3.25 ± 1.29 (means ± SD), respectively, after 2 and 4 hours of oxalate intake (n = 8). The magnitude of the change in the ratio was significantly greater in the case with simultaneous intake of sodium chloride and sodium oxalate in comparison to the case with an intake of sodium oxalate alone (P < 0.05 and P < 0.01 after 2 and 4 hours of intake of oxalate, respectively). In subjects with an intake of sodium chloride alone, the change in calcium-creatinine ratio was 49.07 ± 29.96 and 0.363 ± 0.309 (means ± SD), respectively, after 2 and 4 hours of sodium chloride intake (n = 3). The results suggest that high sodium intake can be one of the risk factors for urolithiasis.

Environmental factors in the pathophysiology of recurrent idiopathic calcium urolithiasis (RCU), with emphasis on nutrition

A number of environmental factors are under discussion as possibly implicated in the etiology of RCU. On the basis of data in the literature and our own results, we attempted a critical weighting up of the possible contributions of climate, pollution, stress, nutrition in general and especially oxalate and minerals in the nutrition. It was concluded that there is a need for more in-depth research into the response of the body to challenges from the environment, in particular nutrition.