Abstract: Objective To study the protective effect of astragalus injection on neurons that surround intracerebral hemorrhage（ICH）in rats. Method ICH model was established by injecting collagenase Ⅶ into the brain of rat. These rats in every group were graded according to the neurological function after analepsia. Immunohistochemical staining technique was used to demonstrate expressions of Bcl-2 and Bax protein. The ultrastructure of neurons that surround intracerebral hemorrhage in rats was observed by transmission electron microscope. Results The positive expression of Bcl-2 in treatment group was higher than that in model group（P<0.01)；However the positive expression of Bax in treatment group degraded prominently (P<0.01). The protein ratio of Bcl-2/Bax increased. Comparing with 0 hour,6 hours treatment group after surgery, the positive expression of Bcl-2 and Bax in 24 hours treatment group after surgery had prominently difference（EM>P/EM><0.05). The positive expression of Bcl-2 in 0 hour treatment group and 6 hours treatment group had no prominently difference（EM>P/EM>＞0.05). The ultrastructure of neuron in normal group was common, however, it was destroyed seriously in model group. The ultrastructure of neuron in astragalus treatment group improved obviously compared with model group. The ultrastructure of neuron in 0 hour,6 hours treatment group after ICH was better than in 24 hours treatment group. Quantitation analysis of nerve synapse displayed that the number of nerve synapse increased prominently in treatment group than in model group（EM>P/EM><0.01)；Meanwhile, the synaptic cleft became narrow conspicuously（EM>P/EM><0.01）；The compact area behind synapse thickened obviously（EM>P/EM><0.01）. The visual parameters of nerve synaptosome in 24 hours treatment group after surgery were different compared with 0 hour,6 hour

Key words: Intracerebral hemorrhage, Astragalus, Synapse, Immunohistochemistry, Rat