AJP - Renal Physiology, Vol 237, Issue 3 167-F174, Copyright © 1979 by American Physiological Society
Optical techniques for the evaluation of epithelial transport processes
K. R. Spring
Light microscopic observation of living epithelial tissues is a powerful
analytical tool in the investigation of solute and water transport. New
techniques in quantitative microscopy permit the determination of
epithelial cell size and shape as well as accurate measurements of lateral
intercellular space dimensions. Traditional techniques for the study of
epithelial cell function may be used in conjunction with continuous
quantitation of tissue morphology. Fluorescent probes of membrane, cell,
and interspace function may be monitored at low light levels to obtain
information about the dynamic behavior of the preparation. Application of
some of these methods to the Necturus gallbladder epithelium has enabled
determination of lateral cell membrane compliance, the hydrostatic pressure
equivalent to active transport, the intracellular NaCl transport pool, the
rate of active NaCl transport, and the flux of NaCl into the cell across
the apical membrane. Possible future applications of optical techniques
include measurement of water permeability, solute reflection coefficients,
fluid flow paterns, and interspace osmolality.
