Effects of high dose intraperitoneal cytosine arabinoside on the radiation tolerance of the rat spinal cord.

The effect of intraperitoneal high dose (9 g/kg) Cytosine Arabinoside (Ara-C) on the early delayed radiation response of the rat cervical spinal cord has been studied. When given 2 hrs before irradiation, systemically administered Ara-C significantly reduces the isoeffect doses for the induction of paralysis due to white matter necrosis by a factor of approximately 1.2 for both a single irradiation treatment and for a two fraction irradiation with 24 hr interval. No effect on the latency time to develop paralysis was recorded.