CHANGES IN EXPRESSION OF CILIARY NEUROTROPHIC FACTOR (CNTF) AND CNTF-RECEPTOR-ALPHA AFTER SPINAL-CORD INJURY

To determine if ciliary neurotrophic factor (CNTF) is involved in the response to spinal cord injury, we studied changes in the expression o f CNTF and that of its receptor, CNTF-receptor alpha (CNTFR alpha), in the rat spinal cord after a unilateral spinal cord hemisection. Using in situ hybridization, we found that CNTFR alpha mRNA levels in spina l cord motoneurons increased dramatically by 1 day after hemisecting t he spinal cord at T2. This increase in expression was present only in motoneurons caudal, but not rostral, to the lesion. In addition, we de tected increased levels of CNTF mRNA in the spinal cord white matter, also by 1 day following injury. Unlike CNTFR alpha, however, the incre ase in CNTF mRNA was evident both rostral and caudal to the lesion. Le vels of both CNTF and CNTFR alpha mRNA declined between 1 and 5 days, and by 10 days they were not significantly different from normal anima ls. These findings suggest that CNTF may play a local role in the resp onse to spinal cord injury. (C) 1997 John Wiley & Sons, Inc.