Y. Akaneya et al., ENHANCEMENT OF CHOLINE-ACETYLTRANSFERASE ACTIVITY IN COCULTURE OF RATSEPTAL AND HIPPOCAMPAL-NEURONS, Brain research, 642(1-2), 1994, pp. 38-46
We report that choline acetyltransferase (ChAT) activity and neuronal
survival were enhanced in rat septal neurons cocultured with hippocamp
al neurons. The enhancement of ChAT activity also occurred as a result
of the addition of hippocampal conditioned medium (HpCM). When septal
neurons from embryonic day 17 (E17) rats were cocultured with hippoca
mpal neurons, ChAT activity was increased 2-fold compared with homogen
eous culture of septal neurons. By contrast, no increase in ChAT activ
ity was observed in coculture of septal and neocortical neurons. Treat
ment with HpCM obtained from cultured E19 rat hippocampal neurons enha
nced the ChAT activity of E17 rat septal neurons. The enhancement of C
hAT activity caused by coculture with hippocampal neurons and that cau
sed by the addition of HpCM were not blocked by the addition of anti-n
erve growth factor (NGF) antibody, suggesting that NGF, which is known
to increase the ChAT activity of septal neurons both in vivo and in v
itro, did not participate in the increase of ChAT activity. These find
ings indicate that possible target-derived neurotrophic factor(s), oth
er than NGF, from hippocampal neurons enhance(s) the ChAT activity of
septal neurons.