TY - JOUR
T1 - Nerve growth factor prevents apoptotic cell death in injured central cholinergic neurons
AU - Wilcox, Barbara J.
AU - Applegate, Michael D.
AU - Portera‐Cailliau, Carlos
AU - Koliatsos, Vassilis E.
PY - 1995/9/4
Y1 - 1995/9/4
N2 - Experimental lesions have been widely used to induce neuronal degeneration and to test the ability of trophic molecules to prevent lesion‐induced alterations, but these studies have not demonstrated unequivocally that afflicted neurons die as a result of these manipulations. The documentation of neuronal death in the above‐described models and the time when it occurs after injury are crucial for the interpretation of trophic effects. In the present study, we combined multiple approaches to investigate the nature of retrograde neuronal changes in holinargic neurons of the medial septal nucleus (MSN) after complete, unilateral transection of the fimbria‐fornix (F‐F). Projection neurons of the MSN were prelabeled with the fluorescent tracer Fluoro‐gold (FG) 1 week prior to lesion. By counting both FG‐labeled and choline acetyltransferase (ChAT)‐immunoreactive neurons in the MSN at multiple time points postaxotomy, we differentiated the phenotypic response to injury from the degenerative process and established a critical time between the third and fourth weeks postaxotomy, during which ∼ 50% of fluorescent perikarya disappear. Working in the previous time window, we identified dying cells by electron microscopy (EM) and terminal transferase‐mediated (TdT) deoxyuridine triphosphate (d‐UTP)‐biotin nick end labeling (TUNEL) and showed that MSN neurons die via apoptosis, beginning at 16 days postaxotomy. An additional group of animals was allowed to survive for 1 month (i.e., 10 days after cell death has been completed); during this period, animals were treated with intraventricular nerve growth factor (NGF). Quantitative analysis of surviving cholinergic perikarya showed that NGF prevented retrograde degeneration of the majority of neurons. In concert, the results of the present study establish that NGF does not merely protect the phenotype but also prevents cell death in lesioned central cholinergic neurons. © 1995 Wiley‐Liss, Inc.
AB - Experimental lesions have been widely used to induce neuronal degeneration and to test the ability of trophic molecules to prevent lesion‐induced alterations, but these studies have not demonstrated unequivocally that afflicted neurons die as a result of these manipulations. The documentation of neuronal death in the above‐described models and the time when it occurs after injury are crucial for the interpretation of trophic effects. In the present study, we combined multiple approaches to investigate the nature of retrograde neuronal changes in holinargic neurons of the medial septal nucleus (MSN) after complete, unilateral transection of the fimbria‐fornix (F‐F). Projection neurons of the MSN were prelabeled with the fluorescent tracer Fluoro‐gold (FG) 1 week prior to lesion. By counting both FG‐labeled and choline acetyltransferase (ChAT)‐immunoreactive neurons in the MSN at multiple time points postaxotomy, we differentiated the phenotypic response to injury from the degenerative process and established a critical time between the third and fourth weeks postaxotomy, during which ∼ 50% of fluorescent perikarya disappear. Working in the previous time window, we identified dying cells by electron microscopy (EM) and terminal transferase‐mediated (TdT) deoxyuridine triphosphate (d‐UTP)‐biotin nick end labeling (TUNEL) and showed that MSN neurons die via apoptosis, beginning at 16 days postaxotomy. An additional group of animals was allowed to survive for 1 month (i.e., 10 days after cell death has been completed); during this period, animals were treated with intraventricular nerve growth factor (NGF). Quantitative analysis of surviving cholinergic perikarya showed that NGF prevented retrograde degeneration of the majority of neurons. In concert, the results of the present study establish that NGF does not merely protect the phenotype but also prevents cell death in lesioned central cholinergic neurons. © 1995 Wiley‐Liss, Inc.
KW - Alzheimer's disease
KW - basal forebrain
KW - hippocampus
KW - medial septum
KW - trophic factors
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U2 - 10.1002/cne.903590405
DO - 10.1002/cne.903590405
M3 - Article
C2 - 7499548
AN - SCOPUS:0029126251
SN - 0021-9967
VL - 359
SP - 573
EP - 585
JO - Journal of Comparative Neurology
JF - Journal of Comparative Neurology
IS - 4
ER -