AJP - Lung Cellular and Molecular Physiology, Vol 267, Issue 6 766-L774, Copyright © 1994 by American Physiological Society
Immunolocalization of glutathione S-transferase isoenzymes in bronchiolar epithelium of rats and mice
M. J. Lee and D. Dinsdale
Medical Research Council Toxicology Unit, Leicester, United Kingdom.
Ultrastructural immunocytochemistry, using antisera raised against specific
subunits of glutathione S-transferases, indicated differences in the
intracellular compartmentalization of these enzymes in the bronchiolar
epithelia of rats and mice. Antisera raised against subunits of the
alpha-class derived from both rats (Ya) and mice (Yc) labeled secretory
granules in Clara cells of rats, but not mice, and they also labeled
mitochondria throughout murine bronchioles. In contrast, antiserum to a
mu-class subunit derived from rats (Yb1) did not result in any labeling
over the Clara cell granules of rats but produced intense labeling over
those of mice. Antiserum raised against a rat-derived pi-class subunit (Yp)
did not label Clara cell granules or mitochondria in either rats or mice
but produced a slight concentration of label over the nuclei of murine
cells. Variations in the distribution of glutathione S-transferases may
contribute to interspecies differences in the sensitivity of particular
lung cells to toxins. Isoenzymes of glutathione S-transferase, secreted
into the bronchioles of rats and mice, may help to protect the epithelium
from extracellular toxins.
