Related Experiment Video

Updated: Jun 19, 2026

Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium
08:46

Implementing Patch Clamp and Live Fluorescence Microscopy to Monitor Functional Properties of Freshly Isolated PKD Epithelium

Published on: September 1, 2015

The endogenous modulators of Ca2+-Mg2+-dependent ATPase in children with chronic kidney disease (CKD)

Dorota Polak-Jonkisz1, Leszek Purzyc, Krystyna Laszki-Szczachor

  • 1Department of Pediatric Nephrology, Wroclaw Medical University, Poland.

Nephrology, Dialysis, Transplantation : Official Publication of the European Dialysis and Transplant Association - European Renal Association
|October 27, 2009
PubMed

Insights

Children with chronic kidney disease (CKD) show increased erythrocyte calcium levels due to decreased Ca(2+)-Mg(2+)-dependent ATPase (PMCA) activity, calmodulin deficiency, and a dysregulated calpain-calpastatin (CANP-CAST) system.

Area of Science:

  • Pediatric Nephrology
  • Cellular Physiology
  • Biochemistry

Background:

  • Chronic kidney disease (CKD) disrupts calcium homeostasis, leading to elevated intracellular calcium in erythrocytes.
  • Maintaining calcium gradients requires complex cellular regulation, which is compromised in CKD.

Purpose of the Study:

  • To evaluate the activity of the Ca(2+)-Mg(2+)-dependent ATPase (PMCA), calmodulin, and the calpain-calpastatin (CANP-CAST) system in erythrocytes of children with CKD stages II-IV.
  • To understand the role of these systems in erythrocyte calcium dysregulation in pediatric CKD.

Main Methods:

  • Studied 36 children with CKD (stages II-IV) and 30 healthy controls.
  • Measured serum intact parathormone, total calcium, and creatinine.
  • Assessed red blood cell free cytosolic calcium (Ca(i)(2+)), PMCA and basal PMCA (bPMCA) activity, calmodulin (CALM), CANP, and CAST concentrations.

Main Results:

  • Erythrocyte Ca(i)(2+) concentrations were significantly higher in all CKD groups compared to controls.
  • PMCA and bPMCA activities were lower in CKD patients.
  • Calmodulin concentrations were decreased, while CANP-CAST system activity showed complex alterations across CKD stages.

Conclusions:

  • Intracellular calcium homeostasis is disturbed in pediatric CKD, worsening renal function.
  • Decreased PMCA activity, calmodulin deficiency, and dysregulated CANP-CAST system contribute to elevated erythrocyte calcium.
  • The findings highlight multifactorial mechanisms underlying calcium dysregulation in pediatric CKD.
Abstract

More Related Videos

Purification of the Sarco-Endoplasmic Reticulum Ca2+-ATPase from Rabbit Muscle08:37

Purification of the Sarco-Endoplasmic Reticulum Ca2+-ATPase from Rabbit Muscle

Published on: March 21, 2025

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry10:24

Cytosolic Calcium Measurements in Renal Epithelial Cells by Flow Cytometry

Published on: October 28, 2014

Related Concept Videos

ATP Synthase: Mechanism01:48

ATP Synthase: Mechanism

In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased ATP...
ATP Driven Pumps III: V-type Pumps01:30

ATP Driven Pumps III: V-type Pumps

V-type pumps are ATP-driven pumps found in the vacuolar membranes of plants, yeast, endosomal and lysosomal membranes of animal cells, plasma membranes of a few specialized eukaryotic cells, and some prokaryotes. They are also known as the V1Vo-ATPase, that couple ATP hydrolysis to transport protons against a concentration gradient.
The peripheral or cytosolic V1 domain with eight subunits is involved in ATP hydrolysis. The integral or transmembrane V0 domain containing at least five subunits...
Calmodulin-dependent Signaling01:16

Calmodulin-dependent Signaling

Calmodulin (CaM) is a calcium-binding protein in eukaryotes that controls various calcium-regulated cellular processes. It has four calcium-binding sites that bind calcium to form the calcium-calmodulin ( Ca2+-CaM) complex. GPCR stimulation increases the calcium levels in the cells that bind to CaM and induces a conformational change.
The Ca2+-CaM complex does not have enzymatic activity by itself. Instead, the complex binds downstream target proteins, including membrane proteins or enzymes,...
Chronic Kidney Disease III: Interprofessional Care01:28

Chronic Kidney Disease III: Interprofessional Care

Chronic kidney disease (CKD) requires collaborative and comprehensive management. CKD progresses through stages and can lead to end-stage kidney disease (ESKD) if untreated. Interprofessional collaboration and patient education are crucial, enabling patients to manage their health and improve their quality of life.Diagnostic approach for chronic kidney diseaseThe diagnosis of CKD primarily focuses on the glomerular filtration rate (GFR), which assesses kidney function by measuring how well...
ATP Driven Pumps II: P-type Pumps01:34

ATP Driven Pumps II: P-type Pumps

The P-type pumps are a large family of integral membrane transporter ATPases. They are divided into five major types based on substrate specificity, from I to V.
A typical P-type pump has three cytosolic domains: nucleotide-binding (N), phosphorylation (P), and activator (A) domains. These domains are connected to the membrane-spanning helices by short amino acid segments. ATP hydrolysis and covalent phosphoenzyme intermediate formation are crucial parts of the catalytic cycle. At the highly...
Chronic Kidney Disease I: Introduction01:25

Chronic Kidney Disease I: Introduction

Chronic Kidney Disease (CKD) arises when the kidneys progressively lose their ability to function, ultimately leading to end-stage renal disease. At this advanced stage, the kidneys can no longer filter waste or maintain essential body functions, requiring renal replacement therapy (RRT) through dialysis or a kidney transplant for survival.Early-stage chronic kidney disease and detection challengesIn CKD's early stages, symptoms often remain absent because healthy nephrons compensate for...