Related Experiment Video

Updated: Jun 22, 2026

Measuring Cation Transport by Na,K- and H,K-ATPase in Xenopus Oocytes by Atomic Absorption Spectrophotometry: An Alternative to Radioisotope Assays
12:48

Measuring Cation Transport by Na,K- and H,K-ATPase in Xenopus Oocytes by Atomic Absorption Spectrophotometry: An Alternative to Radioisotope Assays

Published on: February 19, 2013

Drug modulation of transductor function of Na+,K+-ATPase

E V Lopatina1, V A Pennyaynen, I V Rogachevskyi

  • 1Department of Experimental Pharmacology, V. A. Almazov Federal Center of the Heart, Blood, and Endocrinology, Federal Agency for Medical Technologies, St. Petersburg, Russia. evl112@infran.ru

Bulletin of Experimental Biology and Medicine
|June 4, 2009
PubMed

Insights

Ouabain-calcium complexes modulate Na+,K+-ATPase function. Removing calcium prevents ouabain from inhibiting neurite growth, proving calcium

Area of Science:

  • Biochemistry
  • Cell Biology
  • Neuroscience

Background:

  • Na+,K+-ATPase is a crucial ion pump in cell membranes.
  • Ouabain is a known inhibitor of Na+,K+-ATPase.
  • The role of calcium in ouabain's interaction with Na+,K+-ATPase is not fully understood.

Purpose of the Study:

  • To investigate the hypothesis that ouabain-Ca2+ chelate complexes modulate Na+,K+-ATPase transductor function.
  • To elucidate the mechanism of ouabain-Ca2+-Na+,K+-ATPase ligand-receptor complex formation.
  • To determine the necessity of free calcium for ouabain's effect on neurite growth.

Main Methods:

  • Organotypic tissue culture.
  • Quantum chemical estimations.
  • Calcium removal using EGTA.

Main Results:

  • Experimental evidence supports the modulation of Na+,K+-ATPase by ouabain-Ca2+ complexes.
  • Two distinct Ca2+ ion chelation modes by ouabain were identified computationally.
  • Ouabain did not inhibit neurite growth in explants when free calcium was removed.

Conclusions:

  • The ouabain-Ca2+-Na+,K+-ATPase complex formation, likely via ion-ion bonds, triggers enzyme transductor function.
  • Free calcium is essential for ouabain's inhibitory effect on neurite outgrowth.
  • This study clarifies the calcium-dependent mechanism of ouabain action on Na+,K+-ATPase.

More Related Videos

Measuring Nucleotide Binding to Intact, Functional Membrane Proteins in Real Time08:33

Measuring Nucleotide Binding to Intact, Functional Membrane Proteins in Real Time

Published on: March 11, 2021

Study of the Functions and Activities of Neuronal K-Cl Co-Transporter KCC2 Using Western Blotting10:08

Study of the Functions and Activities of Neuronal K-Cl Co-Transporter KCC2 Using Western Blotting

Published on: December 9, 2022

Related Concept Videos

Active Transport01:14

Active Transport

Active transport is a critical biological process that allows cells to move solutes against an electrochemical gradient. This process requires direct energy input and is characterized by its selectivity, saturability, and susceptibility to competitive inhibition.
Primary active transporters, like Na+, K+ and -ATPase, directly utilize ATP to move ions across the membrane. These transporters play significant roles in various physiological processes. For instance, Na+, K+ and -ATPase maintain...
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...
Primary Active Transport01:29

Primary Active Transport

In contrast to passive transport, active transport involves a substance being moved through membranes in a direction against its concentration or electrochemical gradient. There are two types of active transport: primary active transport and secondary active transport. Primary active transport utilizes chemical energy from ATP to drive protein pumps embedded in the cell membrane. With energy from ATP, the pumps transport ions against their electrochemical gradients—a direction they would not...
Primary Active Transport01:47

Primary Active Transport

In contrast to passive transport, active transport involves a substance being moved through membranes in a direction against its concentration or electrochemical gradient. There are two types of active transport: primary active transport and secondary active transport. Primary active transport utilizes chemical energy from ATP to drive protein pumps that are embedded in the cell membrane. With energy from ATP, the pumps transport ions against their electrochemical gradients—a direction they...
ATP Driven Pumps I: An Overview01:27

ATP Driven Pumps I: An Overview

ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and are...