CNTF OR (-)-DEPRENYL IN IMMATURE RATS - SURVIVAL OF AXOTOMIZED FACIALMOTONEURONS AND WEIGHT-LOSS

The application of ciliary neurotrophic factor (CNTF) to the cut ends of transected facial nerves in newborn rats has been reported to reduc e the death of facial motoneurons (FMns) axotomized by the transection . Systemically delivered CNTF has been found to cause cachexia in adul t mice. We compared the influence of dosage of CNTF and (-)-deprenyl o n FMn death, weight loss, and animal survival in rat pups that underwe nt facial nerve transection at the 14th postnatal day (P14). CNTF was administered by osmotic mini-pumps connected to tubing ending either i ntrathecally or extrathecally near the craniocervical junction. CNTF c aused weight loss and animal death that was similar to the cachexia re ported in mice if administered in amounts of 1.1 mu g/day or greater. At the same doses, intrathecal CNTF was more effective than extratheca l CNTF in inducing the cachexia. (-)-Deprenyl did not alter animal sur vival or weight gain, even at high doses (10 mg/kg every 2 days). Intr athecal CNTF and intraperitoneal (-)-deprenyl, but not extrathecal CNT F, significantly increased the survival of the axotomized FMns. (-)Dep renyl administered twice daily at 0.01 mg/kg was considerably more eff ective than CNTF in increasing FMn survival due to the limitation on C NTF dosage caused by the animal death. (C) 1995 Wiley-Liss, Inc.