Bs. Bregman et al., TRANSPLANTS AND NEUROTROPHIC FACTORS PREVENT ATROPHY OF MATURE CNS NEURONS AFTER SPINAL-CORD INJURY, Experimental neurology, 149(1), 1998, pp. 13-27
Axotomy of mature rubrospinal neurons leads to a substantial atrophy o
f these neurons within days after surgery. In addition, these neurons
do not successfully regenerate following axotomy. The relationship of
atrophy to regenerative failure is not clear, and the signals which re
gulate these events have not been identified. However, it is possible
that the atrophy of these neurons plays a role in preventing regenerat
ion. In the present study, we evaluated the hypothesis that interventi
ons which have been shown to promote growth of axotomized CNS neurons
are also capable of reversing the axotomy-induced atrophy. To test thi
s hypothesis, adults rats received thoracic spinal cord hemisection al
one or in combination with transplants of fetal spinal cord tissue and
/or neurotrophic factor support. Our data indicate that application of
either transplants or neurotrophic factors partially reverse the axot
omy-induced atrophy in rubrospinal neurons, but that both intervention
s together reverse the atrophy completely. These results suggest that
the same pathways that are activated to enhance growth of rubrospinal
neurons after axotomy may also be involved in the maintenance of cell
morphology. (C) 1988 Academic Press.