Journal of Neuroscience, Vol 6, 1606-1612, Copyright © 1986 by Society for Neuroscience
Gradient of extrajunctional acetylcholine receptors early after denervation of mammalian muscle
TA Levitt-Gilmour and MM Salpeter
After denervation, the number of acetylcholine receptors (AChR) found
within the endplate band of skeletal muscle increases transiently by about
twofold. In this study, we used EM autoradiography to show that this
increased endplate band label is not due to an elevated site density of
receptors at the junctional folds. Rather, AChR site density within 500
microns of the endplate was found to be 4 X higher than in non-endplate
areas defined as greater than 2 mm from the endplate. This nonuniform
distribution of extrajunctional AChR early after denervation could
represent a transient gradient, similar to that reported shortly after
innervation during development.