Plasma cortisol and urinary excretion of water, sodium, potassium, calcium and magnesium have been studied in the rat after application of heat stress. There was a significant increase in plasma cortisol level after exposure to heat. During heat stress complete cessation of urine formation was observed. In the next 30 min there was statistically significant increase in the urinary excretion of ...

Studies carried out with tracer doses of radiostrontium (Sr85) in man have revealed qualitative similarities but quantitative differences in metabolism of strontium and calcium (1-5). The principle of qualitative correlation between urinary excretion of calcium and of radiostrontium has been utilized in investigations of the removal of radiostrontium from man (6). It has been shown that elimina...

A HIGH incidence of phosphate urinary calculi in sheep has been associated with the feeding of rations containing dibasic potassium phosphate (Lindley et al., 1953; Elam et al., 1956, 1957). Further, Lindley et al. (1953) observed elevated plasma phosphorus levels under these conditions. Emerick et al. (1959) observed high plasma phosphorus levels in lambs subsequently afflicted with urinary mi...

Urine specimens were collected from 26 normal subjects, 10 patients with proven primary hyperparathyroidism, and eight patients with hypercalcaemia due to other causes. After overnight urine concentration, an oral water load was given to induce a diuresis and provide urine specimens with a relatively wide range of creatinine concentration for each subject. In normal subjects the urinary calcium...

Tiselius proposed simplified estimates of the ion-activity products of calcium oxalate, calcium phosphate, and brushite as the AP(CaOx) index, the AP(CaP) index, and the AP(Bru) index, respectively, which allowed assessment of the urinary saturation levels of these lithogenic substances. A number of urinary variables (calcium, magnesium, oxalate, phosphate, citrate, urine volume, and pH) are ne...

Studies in 24 recurrent oxalate stone-formers have shown that values for urinary calcium excretion for this group on at-home diets vary significantly (P less than 0.001) more than values for creatinine excretions. By placing stone-formers on controlled in-hospital diets and measuring their calcium excretions, we were able to predict probable outpatient hypercalciuria (greater than 7.5 mmol/day)...

We carried out clearance studies in nine healthy adults and four patients with hypoparathyroidism before and after inducing stable metabolic acidosis with either NH(4)Cl or acetazolamide. Clearances were repeated in seven normal subjects and three of the patients 3 days after stopping these agents.During acidosis in the normal subjects, serum ultrafilterable calcium concentration rose significa...

BACKGROUND Hypercalciuria is a frequent characteristic of hypertension. In this report we extend our earlier studies investigating the role of renal interstitial fluid calcium (ISF(Ca))(2+) as a link between urinary calcium excretion and blood pressure in the Dahl salt-sensitive (DS) hypertensive model. METHODS Dahl salt-sensitive and salt-resistant (DR) rats were placed on control (0.45%) an...

INTRODUCTION Even though dehydration could aggravate formation of urinary calculi, the effects of fluid and food restriction on calculus formation is not thoroughly defined. The purpose of this study is to evaluate the effects of fluid and food restriction in Ramadan fasting on urinary factors in kidney and urinary calculus formation. MATERIALS AND METHODS Fifty-seven men aged 30 to 55 years ...

Transl Androl Urol 2014;3(3):241 www.amepc.org/tau The regulation of dietary and supplemental calcium intake in relation to urinary stone disease is not well understood (1). For instance, why do most patients with primary hyperparathyroidism with markedly increased serum and urinary calcium not have a history of urinary stone disease? There must be other factors involved in stone formation. Cal...