B. Pfeiffer et al., GLYCOGEN-PHOSPHORYLASE ACTIVITY AND IMMUNOREACTIVITY DURING PRENATAL AND POSTNATAL-DEVELOPMENT OF RAT-BRAIN, Histochemistry, 100(4), 1993, pp. 265-270
Catalytic activity and immunoreactivity of glycogen phosphorylase were
studied in pre- and postnatal rat brain. The catalytic activity was a
ssayed in brain homogenates; immunoreactivity was investigated by immu
noblot analysis using a monoclonal anti-bovine brain glycogen phosphor
ylase antibody. The cellular localization and intensity of immunoreact
ivity were analysed on paraffin-embedded sections utilizing the same m
onoclonal antibody. The catalytic activity increased 10-fold from embr
yonic day 16 to adult; immunoreactivity became detectable on embryonic
day 16 and increased in intensity as the enzyme activity rose to adul
t values. The first cellular elements to be stained immunohistochemica
lly were ependymal cells lining the ventricles, ependymal cells of the
choroid plexus, meningeal cells and a selected population of neurons
in the brain stem. The immunoreactivity of plexus cells and meningeal
cells was reduced or absent in the adult rat brain. The earliest appea
rance of glycogen phosphorylase immunoreactivity in astroglial cells w
as seen at postnatal day 9 in the hippocampus. The staining pattern of
the adult brain was reached at day 22 post partum. The developmental
changes in glycogen deposition and in glycogen phophorylase activity a
nd immunoreactivity may indicate a variable physiological role of glyc
ogen metabolism for different cell types in the pre- and postnatal per
iods.