The Primary Research Of Chitosan For The Local Sustained-releasing Chemotherapeutic Carrier In The Rat Brain

Objective To study the effect of chitosan on the brain (including neuron and neuronglial cell), discuss the biocompatibility of chitosan in brain and evaluate the feasibility of chitosan for the intracranial carrier of the local sustained-releasing chemotherapy by comparing the contents of NSE and S-100 in bloods of experimental group ( chitosan group) and control group (physiological saline group).Methods 64 adult SD rats were randomly divided into two groups, chitosan group and physiological saline group. Each group was further divided randomly into 3, 7, 14 and 30 day subgroups (n=8). Intracraninal injection of 50μl of chitosan or physiological saline was performed respectively in rats of both the groups. Respectively on 3rd, 7th, 14th and 30th day after the injection, the rats were sacrificed to collect blood samples, where the serum contents of neuron-specific enolase (NSE) and S-100 protein were determined by enzyme-linked immuno-sorbent assay (ELISA), and drew brain to hematoxylin-eosin (HE) staining to histological examination to observe local reaction of surrounding tissues of the transplants after the transplantation.Results The levels of NSE in 3, 7, 14 and 30day subgroup of chitosan group was respectively 4.457±0.567, 1.222±0.137, 1.140±0.256 and 1.2 73± 0.291μgL~-1. NSE levels in four subgroups of physiological saline was 4.318±0.398, 1.307±0.188, 0.975±0.26 and 1.1400.160μgL~-1. The levels of S-100 in 3, 7, 14 and 30day subgroup of chitosan group was respectively 0.661±0.108, 0.500±0.074, 0.401±0.046 and 0.357±0.052 μgL~-1. S-100 levels in four subgroups of physiological saline was 0.583±0.099, 0.494±0.081, 0.398±0.065 and 0.369±0.042μgL~-1. The same repair could be observed by HE staining. The traumatic focus was eventually filled with neuronglial cell and nerve fiber. There were no significant differences in serum NSE and S-100 protein levels and pathological changes in the brain between both chitosan group and physiological saline group.Conclusions These results primarily indicated that chitosan had no side- effects when being intracranially injected. And it may be used for the intracranial carrier of the local sustained-releasing chemotherapy.