The uptake mechanism of Zn2+ through the gill epithelium of freshwater rainbow trout was investigated both in intact animals and in isolated basolateral membranes. Involvement of the apical Ca2+ uptake sites in Zn2+ uptake was examined in vivo by pharmacological manipulation of the apical Ca2+ permeability. The apical entries of Ca2+ and Zn2+, but not Na2+ and Cl-, were inhibited by addition of La to the water. Addition of 1.0 microM La reduced the influxes of Ca2+ and Zn2+ to 22 +/- 3 and 53 +/- 7% (mean +/- SE) of the control value, respectively. Injection of CaCl2 also reduced the branchial influxes of Ca2+ and Zn2+. This treatment decreased the influx of Ca2- to 45 +/- 4% of the control level and the Zn2+ influx to 68 +/- 5%. These results strongly imply that Zn2+ passes across the apical membrane of the chloride cells of the gills via the same pathway as Ca2+. The presence of an active basolateral transporter for Zn2+ was investigated in vitro on isolated basolateral membranes. There was no ATP-dependent or Na2+(-)gradient driven transport of Zn2+ at physiological Zn2+ activities. The same system was used to study potential effects of Zn2+ on the basolateral Ca2+(-)adenosinetri-phosphatase. Zn2+ was found to be a potent blocker of this transporter, causing a mixed inhibitory effect on the ATP driven Ca2+ transport at a free Zn2+ activity of 100 pM.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1152/ajpregu.1996.270.5.R1141 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Histidine Tags in Human Recombinant Alpha B-Crystallin (HSPB5) Proteins Are Detrimental for Zinc Binding Studies.
Biopolymers
March 2025
Department of Chemistry, Bose Institute, Kolkata, India.
The stability of α-crystallin, the major protein of the mammalian eye lens and a molecular chaperone, is one of the most crucial factors for its survival and function. The chaperone-like activity and stability of α-crystallin dramatically increased in the presence of Zn. Each subunit of α-crystallin could bind multiple zinc atoms through inter-subunit bridging and cause enhanced stability.
View Article and Find Full Text PDFEnhancing organic cathodes of aqueous zinc-ion batteries nitro group modification.
Chem Sci
January 2025
School of Chemistry and Chemical Engineering, Anhui University of Technology Ma'anshan 243032 Anhui China
Organic compounds present promising options for sustainable zinc battery electrodes. Nevertheless, the electrochemical properties of current organic electrodes still lag behind those of their inorganic counterparts. In this study, nitro groups were incorporated into pyrene-4, 5, 9, 10-tetraone (PTO), resulting in an elevated discharge voltage due to their strong electron-withdrawing capabilities.
View Article and Find Full Text PDFTargeted Docking of Localized Hydrogen Bond for Efficient and Reversible Zinc-Ion Batteries.
Angew Chem Int Ed Engl
January 2025
Central South University, material science and engineering, 932 Lushan Road, 410083, Changsha, CHINA.
Hydrogen bond (HB) chemistry, a pivotal feature of aqueous zinc-ion batteries, modulates electrochemical processes through weak electrostatic interactions among water molecules. However, significant challenges persist, including sluggish desolvation kinetics and inescapable parasitic reactions at the electrolyte-electrode interface, associated with high water activity and strong Zn2+-solvent coordination. Herein, a targeted localized HB docking mechanism is activated by the polyhydroxy hexitol-based electrolyte, optimizing Zn2+ solvation structures via dipole interaction and reconstructing interfacial HB networks through preferential parallel adsorption.
View Article and Find Full Text PDFMultiple Protophilic Redox-Active Sites in Reticular Organic Skeletons for Superior Proton Storage.
Angew Chem Int Ed Engl
January 2025
Tongji University, School of Chemical Science and Engineering, 1239 Siping Road, 200092, Shanghai, CHINA.
Protons (H+) with the smallest size and fastest redox kinetics are regarded as competitive charge carriers in the booming Zn-organic batteries (ZOBs). Developing new H+-storage organic cathode materials with multiple ultralow-energy-barrier protophilic sites and super electron delocalization routes to propel superior ZOBs is crucial but still challenging. Here we design multiple protophilic redox-active reticular organic skeletons (ROSs) for activating better proton storage, triggered by intermolecular H-bonding and π-π stacking interactions between 2,6-diaminoanthraquinone and 2,4,6-triformylphloroglucinol nanofibrous polymer.
View Article and Find Full Text PDFCotadutide reversible self-assembly based long-acting injectable depot for sustained delivery of GLP-1 glucagon receptor agonists with controlled burst release.
J Control Release
January 2025
Advanced Drug Delivery, Pharmaceutical Sciences, R&D, AstraZeneca, Waltham, MA, USA.
Cota is a lipidated dual GLP-1 and Glucagon receptor agonist that was investigated for the treatment of various metabolic diseases, it is designed for once daily subcutaneous administration. Invasive daily injections often result in poor patient compliance with chronic disease, and here, we demonstrate an innovative strategy of encapsulating reversible cota self-assembled fibers within an in-situ forming depot of low molecular weight poly(lactic-co-glycolic) acid (LWPLGA) for sustained delivery GLP-1 and Glucagon receptor agonist with controlled burst release. This could be a suitable alternative to other sustained delivery strategies for fibrillating peptides.
View Article and Find Full Text PDFWant 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!