PTH stimulates transcellular Ca2+ absorption in renal distal convoluted tubules. The effect of PTH on membrane voltage, the ionic basis of the change in voltage, and the relations between voltage and calcium entry were determined on immortalized mouse distal convoluted tubule cells. PTH (10(-8) M) significantly increased 45Ca2+ uptake from basal levels of 2.81 +/- 0.16 to 3.88 +/- 0.19 nmol min...

PURPOSE OF REVIEW Knowledge of renal Ca2+ reabsorption has evolved greatly in recent years. This review focuses on two recent discoveries concerning passive and active Ca2+ reabsorption. RECENT FINDINGS The thiazide diuretics are known for their hypocalciuric effect. Recently, it has been demonstrated that TRPV5-knockout mice, in which active Ca2+ reabsorption in the distal convoluted tubule ...

Oriental white-backed vultures (Gyps bengalensis; OWBVs) died of renal failure when they ingested diclofenac, a nonsteroidal anti-inflammatory drug (NSAID), in tissues of domestic livestock. Acute necrosis of proximal convoluted tubules in these vultures was severe. Glomeruli, distal convoluted tubules, and collecting tubules were relatively spared in the vultures that had early lesions. In mos...

The sites of action of angiotensin II along the nephron are not well defined and both proximal and distal effects are suggested. Using a microassay that permits measurement ofhormone binding in discrete tubule segments, we determined the binding sites of '25I-angiotensin II along the nephron of Sprague-Dawley rats. Specific binding in proximal convoluted tubule (PCT) (at 250C, pH 7.4) was linea...

Rat kidney contains two distinct glutaminase isoenzymes. One requires phosphate for activity; the other is phosphateindependent but is activated 15-fold by maleate. By taking advantage of differences in activators and pH optima, specific assays were devised for each isoenzyme. Their distribution was then examined in individual structures of nephrons dissected from lyophilized 20-M sections of k...

Human calcium transporting tissues were examined to determine whether they contained a protein similar to the Ca++-Mg++ adenosine triphosphatase (Ca++-Mg++ATPase) pump of the human erythrocyte membrane. Tissues were processed for immunoperoxidase staining using monoclonal antibodies against purified Ca++-Mg++ATPase. In human kidneys, specific staining was found only along the basolateral membra...

Elucidation of the gene defects responsible for many disorders of renal fluid and electrolyte homeostasis has provided new insights into normal and abnormal physiology. Identifying the causes of Gitelman's and Bartter's syndromes has greatly enhanced our understanding of ion transport by thick ascending limb and distal convoluted tubule cells. Despite this information, several phenotypic featur...

Metabolic acidosis is a common clinical condition that is caused by a decrease in blood pH and bicarbonate concentration. Increased extraction and mitochondrial catabolism of plasma glutamine within the renal proximal convoluted tubule generates ammonium and bicarbonate ions that facilitate the excretion of acid and partially restore acid-base balance. Previous studies identified only a few mit...

the effect of tillage (conventional and zero tillage), crop establishment (raised-bed and flat-bed), and weed management practices (herbicide alone and integrated approach) was studied on productivity, profitability, nutrient uptake and physico-chemical properties of soil in soybean–wheat cropping system, at new delhi during 2010–2012. sixteen treatment combinations consisting of four tillage a...

Placental vasculature, in particular the relationship between maternal and fetal blood circulations, has been a contentious issue for a long time. It was indeed a matter of dispute whether or not the fetal blood circulation was separate from or continuous with the circulation of the mother as stated by the Roman physician Galen (129–200). The Renaissance anatomist Julius Caesar Arantius (1530–1...