Related Experiment Video
Updated: Jul 12, 2026

Quantifying Glomerular Permeability of Fluorescent Macromolecules Using 2-Photon Microscopy in Munich Wistar Rats
Published on: April 17, 2013
Water permeability of brush border membrane vesicles from kidney proximal tubule
G Soveral1, R I Macey, T F Moura
1Instituto de Tecnologia Química e Biológica (ITQB), Universidade Nova de Lisboa, Oeiras, Portugal.
Abstract:
Brush border membrane vesicles (BBMV) maintain an initial hydrostatic pressure difference between the intra- and extravesicular medium, which causes membrane strain and surface area expansion (Soveral, Macey & Moura, 1997). This has not been taken into account in prior osmotic water permeability Pf evaluations. In this paper, we find further evidence for the pressure in the variation of stopped-flow light scattering traces with different vesicle preparations. Response to osmotic shock is used to estimate water permeability in BBMV prepared with buffers of different osmolarities (18 and 85 mosM). Data analysis includes the dissipation of both osmotic and hydrostatic pressure gradients. Pf values were of the order of 4 x 10(-3) cm sec-1 independent of the osmolarity of the preparation buffer. Arrhenius plots of Pf vs. 1/T were linear, showing a single activation energy of 4.6 kcal mol-1. The initial osmotic response which is significantly retarded is correlated with the period of elevated hydrostatic pressure. We interpret this as an inhibition of Pf caused by membrane strain and suggest how this inhibition may play a role in cell volume regulation in the proximal tubule.
More Related Videos
09:40Isolation, Characterization, And High Throughput Extracellular Flux Analysis of Mouse Primary Renal Tubular Epithelial Cells
Published on: June 20, 2018
07:06Isolation of Primary Human Proximal Tubule Epithelial Cells and Their Use in Creating a Microphysiological Model of the Renal Proximal Tubule
Published on: May 9, 2025
Related Concept Videos
Drug Elimination by Renal Route: Tubular Secretion
Renal Tubule and Collecting Duct
Proximal Convoluted Tubule (PCT):
The PCT is the initial segment of the renal tubule, extending from the Bowman's capsule that encloses the glomerulus. Its convoluted structure and microvilli-lined cells increase the surface area for reabsorption. The PCT reabsorbs glucose, amino acids, sodium, and water from the filtrate, ensuring essential...
Reabsorption and Secretion in the PCT
Transport mechanisms involving sodium ions (Na+) contribute significantly to solute reabsorption. These mechanisms include symport and antiport processes.
A key example is the...
Reabsorption and Secretion in the Loop of Henle
Reabsorption and Secretion in the DCT and Collecting Duct
The distal part of the DCT, along with the...
Physiology of the Genitourinary System II: Tubular Reabsorption and Secretion