Effect Of The Osmotic Opening Of The Blood-Brain Barrier On The Entry Of The Carboplatin

0bjective To investigate the effect of the osmotic opening of the blood-brain barrier (BBB)on the entry of the carboplatin(CBP), and the difference between intravenous injection and intra-arterial injection.Methods 25 adult rabbits were randomly divided into 5 groups: intravenous injection of carboplatin(A group),intra-arterial injection of carboplatin (B group), intravenous injection of carboplatin and mannitol(C group), intra-arterial injection of carboplatin and mannitol (D group), intravenous injection of Ringer's solution(E group).The plasma and cerebrospinal fluid (CSF) in 5 groups were obtained at 30min after the injections,respectively . The plasma and CSF concentration of carboplatin were measured by HPLC. Then, the rabbits were sacrificed with airinjection and one part of the brain was measured the cerebral water content, another part were dissected for examination by light microscopy after 24 hours. Results was tested with chi square test, Simple-way ANOVA and least-significant-difference(LSD).Results①The mean in 4 groups of CSF concentration of carboplatin at 30min was 1.16±0.31μg/ml;1.83±0.27μg/ml4.87±0.55μg/ml;7.11±0.87μg/ml,respectively.The mean of D group is the highest in 4 groups. There were significant difference between D group and A group,D group and B group,D group and C group,C group and B group, C group and A group,P<0.05.②The mean CSF concentration of plasma at 0.5 hour of 4 groups was5.70% ,8.56%,21.00%,27.61%, respectively. There were significant difference in 4 groups tested with LSD except for A and B group, P>0.05.③The population mean of cerebral water content was 76.63±1.95%. The mean of D group was the lowest, which was 75.86±2.02%. The mean of B group was the highest , which was 77.71±1.63%. The result tested with Simple-way ANOVA was no significant difference.④Histomorphology of brain was no obviously changes by light microscopy.⑤The CSF concentration was not related to sexuality and weight in statistics (p>0.05).Conclusion Enhanced carboplatin delivery to the central nevous system can be attained by osmotic disruption of BBB through the injection of 20% mannitol, and CSF concentration of the intra-arterial injection groups is more than the intravenous injection groups with or not mannitol. There was no difference between intravenous injection and intra-arterial injection when are simply injected with carboplatin. No obviously brain damage was observed in this study.