Sa. Scott et al., INCREASED NGF-LIKE ACTIVITY IN YOUNG BUT NOT AGED RAT HIPPOCAMPUS AFTER SEPTAL-LESIONS, Neurobiology of aging, 15(3), 1994, pp. 337-346
Sympathetic sprouting in the hippocampus following septal denervation
is thought to involve nerve growth factor (NGF). This sprouting respon
se is dramatically reduced in aged rats, but immunological assays reve
al no age-related decline in hippocampal NGF levels. In the present st
udy, both,a bioassay and an immunoassay were used to examine the effec
t of a medial septal lesion on hippocampal NGF levels in young adult (
2-5 months) and aged (24 months) Fischer 344 rats. No significant diff
erences were detected between normal young and aged rats, in agreement
with earlier results. Following medial septal lesions, however, only
young rats demonstrated significant increases in hippocampal NGF-like
activity. These results support the hypothesis that the age-related de
ficit in sympathetic sprouting results from an attenuated neurotrophic
response to hippocampal denervation.