Prevention of apoptosis averts glomerular tubular disconnection and podocyte loss in proteinuric kidney disease.

There is a great need for treatment that arrests progression of chronic kidney disease. Increased albumin in urine leads to apoptosis and fibrosis of podocytes and tubular cells and is a major cause of functional deterioration. There have been many attempts to target fibrosis, but because of the lack of appropriate agents, few have targeted apoptosis.

Oscillometric casual blood pressure normative standards for Swedish children using ABPM to exclude casual hypertension.

Background: Casual blood pressure (CBP) is considered a reliable proxy for cardiovascular health. Although the auscultatory technique is the reference standard method for measuring CBP, oscillometric devices are increasingly being used in children. We sought to establish oscillometric CBP normative standards for Swedish children.

Renal-limited vasculitis in children: a single-center retrospective long-term follow-up analysis.

Pauci-immune renal limited vasculitis (RLV) is a rare and aggressive autoimmune disease. We retrospectively analyzed the renal outcome of 6 children with biopsy proven RLV. Median age at diagnosis was 10.

Prolactin and dopamine 1-like receptor interaction in renal proximal tubular cells.

Prolactin is a natriuretic hormone and acts by inhibiting the activity of renal tubular Na(+)-K(+)-ATPase activity. These effects require an intact renal dopamine system. Here, we have studied by which mechanism prolactin and dopamine interact in Sprague-Dawley rat renal tissue.

Negative reciprocity between angiotensin II type 1 and dopamine D1 receptors in rat renal proximal tubule cells.

Sodium excretion is bidirectionally regulated by dopamine, acting on D1-like receptors (D1R) and angiotensin II, acting on AT1 receptors (AT1R). Since sodium excretion has to be regulated with great precision within a short frame of time, we tested the short-term effects of agonist binding on the function of the reciprocal receptor within the D1R-AT1R complex in renal proximal tubule cells. Exposure of rat renal proximal tubule cells to a D1 agonist was found to result in a rapid partial internalization of AT1R and complete abolishment of AT1R signaling.

Urinary aquaporin-2 in children with acute pyelonephritis.

Children with acute pyelonephritis develop polyuria and have reduced maximum urinary concentration capacity. We studied whether these abnormalities are associated with altered urinary excretion of the water channel aquaporin-2 (AQP2) in the renal collecting duct. AQP2 is the main target for antidiuretic action of arginine vasopressin (AVP), and the urinary excretion of this protein is believed to be an index of AVP signaling activity in the kidney.

The role of endocytosis in renal dopamine D1 receptor signaling.

Desensitization of G-protein-coupled receptors (GPCR) includes receptor endocytosis. This phenomenon is suggested, at least for some receptors, to be associated with receptor resensitization. Here, we examined the role of receptor endocytosis for two different GPCR, the dopamine-1 (D1) receptor and the beta1-adrenoceptor (beta(1)-AR) in renal tissue.

Prolactin, a natriuretic hormone, interacting with the renal dopamine system.

Background: Although prolactin affects sodium and water transport across the plasma membrane and interacts with dopamine in the brain, its role in the kidney is unclear. Here we examined the effect of prolactin and its possible interaction with the intrarenal natriuretic hormone dopamine, on proximal tubular Na(+), K(+)-ATPase activity in vitro and renal function in anesthetized rats.

Methods: Na(+), K(+)-ATPase activity was measured as ouabain-sensitive adenosine triphosphate (ATP) hydrolysis in microdissected proximal tubular segments.

Molecular determinants of sodium and water balance during early human development.

The past decade has seen enormous progress in understanding the renal regulation of salt and water homeostasis. Most of the key transporters have been cloned, and their physiological importance has been revealed from studies of children with inherited diseases and from mutagenesis studies on a cellular level. We are beginning to understand the complexity with which the activity of these transporters is regulated by hormones.

Cellular response to renal hypoxia is different in adolescent and infant rats.

Immature renal tubules are more tolerant to ischemia than mature renal tubules. Here we compared the developmental pattern for some cellular responses evoked by hypoxia and reoxygenation in renal proximal tubules from 10- and 40-day-old rats. Redistribution of Na(+)-K(+)-ATPase from the plasma membrane was studied by confocal microscopy techniques in primary cultured renal proximal tubular cells.

Recruitment of renal dopamine 1 receptors requires an intact microtubulin network.

Renal dopamine1 receptor (D1R) can be recruited from intracellular compartments to the plasma membrane by D1R agonists and endogenous dopamine. This study examines the role of the cytoskeleton for renal D1R recruitment. The studies were performed in LLCPK-1 cells that have the capacity to form dopamine from L-dopa.