We characterized ouabain-insensitive Na+-ATPase activity present in the plasma membrane of Leishmania amazonensis and investigated its possible role in the growth of the parasite. An increase in Na+ concentration in the presence of 1mM ouabain, increased the ATPase activity with a V(max) of 154.1+/-13.5nmol Pi x h(-1) x mg(-1) and a K0.5 of 28.9+/-7.7mM. Furosemide and sodium orthovanadate inhibited the Na+-stimulated ATPase activity with an IC(50) of 270microM and 0.10microM, respectively. Furosemide inhibited the growth of L. amazonensis after 48h incubation, with maximal effect after 96h. The IC50 for furosemide was 840. On the other hand, ouabain (1mM) did not change the growth of the parasite. Taken together, these results show that L. amazonensis expresses a P-type, ouabain-insensitive Na+-ATPase that could be involved with the growth of the parasite.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.exppara.2007.07.001 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enteric Nervous System: Identification of a Novel Neuronal Sensory Network in the Duodenal Epithelium.
J Histochem Cytochem
November 2023
Laboratory of Molecular Physiology, Biophysics and Biochemistry Center, Instituto Venezolano de Investigaciones Científicas (IVIC), Caracas, Venezuela.
The communication between the intestinal epithelium and the enteric nervous system has been considered indirect. Mechanical or chemical stimuli activate enteroendocrine cells inducing hormone secretion, which act on sub-epithelial nerve ends, activating the enteric nervous system. However, we identified an epithelial cell that expresses NKAIN4, a neuronal protein associated with the β-subunit of Na/K-ATPase.
View Article and Find Full Text PDFCeramide-1-Phosphate as a Potential Regulator of the Second Sodium Pump from Kidney Proximal Tubules by Triggering Distinct Protein Kinase Pathways in a Hierarchic Way.
Curr Issues Mol Biol
February 2022
Laboratório de Biomembranas, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Ilha do Fundão, Rio de Janeiro 21941-902, Brazil.
Kidney proximal tubules are a key segment in the reabsorption of solutes and water from the glomerular ultrafiltrate, an essential process for maintaining homeostasis in body fluid compartments. The abundant content of Na in the extracellular fluid determines its importance in the regulation of extracellular fluid volume, which is particularly important for different physiological processes including blood pressure control. Basolateral membranes of proximal tubule cells have the classic Na + K-ATPase and the ouabain-insensitive, K-insensitive, and furosemide-sensitive Na-ATPase, which participate in the active Na reabsorption.
View Article and Find Full Text PDFMechanisms involving Ang II and MAPK/ERK1/2 signaling pathways underlie cardiac and renal alterations during chronic undernutrition.
PLoS One
January 2016
Carlos Chagas Filho Institute of Biophysics, Federal University of Rio de Janeiro, Rio de Janeiro, Brazil; National Institute of Science and Technology for Structural Biology and Bioimaging, Rio de Janeiro, Brazil.
Background: Several studies have correlated protein restriction associated with other nutritional deficiencies with the development of cardiovascular and renal diseases. The driving hypothesis for this study was that Ang II signaling pathways in the heart and kidney are affected by chronic protein, mineral and vitamin restriction.
Methodology/principal Findings: Wistar rats aged 90 days were fed from weaning with either a control or a deficient diet that mimics those used in impoverished regions worldwide.
Inorganic phosphate uptake in Trypanosoma cruzi is coupled to K(+) cycling and to active Na(+) extrusion.
Biochim Biophys Acta
August 2013
Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil.
Background: Orthophosphate (Pi) is a central compound in the metabolism of all organisms, including parasites. There are no reports regarding the mechanisms of Pi acquisition by Trypanosoma cruzi.
Methods: (32)Pi influx was measured in T.
Perinatal Na+ overload programs raised renal proximal Na+ transport and enalapril-sensitive alterations of Ang II signaling pathways during adulthood.
PLoS One
January 2013
Department of Physiology and Pharmacology, Federal University of Pernambuco, Recife, Brazil.
Article Synopsis
- High sodium intake during pregnancy leads to long-term kidney and cardiovascular issues in offspring, specifically affecting sodium transport processes and the renin/angiotensin system (RAS).
- A study on male Wistar rats showed that offspring exposed to high sodium had increased sodium-potassium ATPase activity but impaired response to angiotensin II, along with elevated signs of oxidative stress and inflammation.
- Treatment with the drug enalapril improved some of the sodium transport functions and reduced inflammatory markers, but also caused some unexpected increases in oxidative stress and macrophage infiltration, highlighting complex interactions in kidney health after sodium overload.
Want AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!