Forty SD rats were randomly divided into sham operation group， model group， Tan ⅡA group and miR-132 antagomir group， with 10 rats in each group. The rat models of hypoxic-ischemic encephalopathy were established by double ligation of the common carotid artery and being put into anoxic chamber. The rats in TanⅡA group were intrapeitoneally injected with Tan ⅡA injection （24 mg·kg^－1）， and 2 μg miR-132 negative control （NC） was injected into the bilateral ventricles. The rats in sham operation group and model group were intraperitoneally injected with the same amount of normal saline. After modeling， the rats in miR-132 antagomir group were intraperitoneally injected with tanshinone ⅡA injection （24 mg·kg^－1）， and 2 μg miR-132 antagomir was injected into the bilateral ventricles； the tars in various groups were injected for 7 d. The expression levels and fluorescence intensities of miR-132 in hippocampus tissue of the rats in various groups were detected by real-time fluorescence quantitative PCR（RT-qPCR） and fluorescence in situ hybridization. Modified neurological deficit score was used to evaluate the neural function of the rats in various groups. HE staining was used to observe the pathomorphology of hippocampus tissue of the rats in various groups. TUNEL assay was used to detect the apoptotic rates of neurons in hippocampus tissue of the rats in various groups. The levels of monoamine neurotransmitters in hippocampus tissue of the rats in various groups were detected by enzyme-linked immunosorbent assay （ELISA）. The densities of dendritic spines in hippocampus tissues of the rats in various groups were detected by Golgi staining. The protein expression levels of postsynaptic density-95（PSD-95），growth associated protein-43（GAP-43），microtubule-associated protein-2 （MAP）-2 and brain-derived neurotrophic factor （BDNF） in hippocampus tissue of the rats in various groups were detected by Western blotting method.

Compared with sham operation group， the expression level of miR-132 in the hippocampus tissue and the fluorescence intensity of the rats in model group were significantly decreased （P<0.05）； compared with model group， the expression level of miR-132 in hippocampus tissue and the fluorescence intensity of the rats in Tan ⅡA group were significantly increased （P<0.05）； compared with Tan ⅡA group， the miR-132 expression level in hippocampus tissue and the fluorescence intensity of the rats in miR-132 antagomir group were significantly decreased （P<0.05）. Compared with sham operation group， neurological deficit score of the rats in model group were significantly increased （P<0.05）； compared with model group， the neurological deficit score of the rats in Tan ⅡA group was significantly decreased （P<0.05）； compared with Tan ⅡA group， the neurological deficit score of the rats in miR-132 antagomir group was significantly increased （P<0.05）.The HE staining results showed that the hippocampus tissue of the rats in sham operation group was not damaged；compared with sham operation group， the hippocampus tissue of the rats in model group was seriously damaged；compared with model group， the damage of hippocampus tissue of the rats in Tan ⅡA group was improved；compared with Tan ⅡA group， the hippocampus tissue of the rats in miR-132 antagomir group was seriously damaged. Compared with sham operation group， the apoptotic rate of cells of hippocampal tissue of the rats in model group was significantly increased （P<0.05）； compared with model group， the apoptotic rate of cells of hippocampus tissue in the Tan ⅡA group was significantly decreased （P<0.05）； compared with Tan ⅡA group， the apoptotic rate of cells of hippocampus tissue in miR-132 antagomir group was significantly increased （P<0.05）. Compared with sham operation group， the levels of norepinephrine， dopamine and 5-hydroxytryptamine in hippocampus tissue of the rats in model group were significantly decreased （P<0.05）； compared with model group， the levels of norepinephrine， dopamine and 5-hydroxytryptamine in hippocampus tissue of the rats in Tan ⅡA group were significantly increased （P<0.05）； compared with Tan ⅡA group， the levels of norepinephrine， dopamine and 5-hydroxytryptamine in hippocampus tissue of the rats in miR-132 antagomir group were significantly decreased （P<0.05）. Compared with sham operation group， the density of dendritic spines in hippocampus tissue of the rats in model group was significantly decreased （P<0.05）； compared with model group， the density of dendritic spines in hippocampus tissue of the rats in Tan ⅡA group was significantly increased （P<0.05）； compared with Tan ⅡA group， the density of dendritic spines in hippocampus tissue of the rats in miR-132 antagomir group was significantly decreased （P<0.05）. Compared with sham operation group， the expression levels of PSD-95， GAP-43， MAP-2 and BDNF proteins in hippocampus tissue of the rats in model group were significantly decreased （P<0.05）； compared with model group， the expression levels of PSD-95， GAP-43， MAP-2 and BDNF proteins in hippocampus tissue of the rats in Tan ⅡA group were significantly increased （P<0.05）； compared with Tan ⅡA group， the expression levels of PSD-95， GAP-43， MAP-2 and BDNF proteins in hippocampus tissue of the rats in miR-132 antagomir group were significantly decreased （P<0.05）.

Tan ⅡA can up-regulate the expression of miR-132 in the hippocampus tissue of the neonatal rats with hypoxic-ischemic encephalopathy， and improve the neurological function and pathological damage of hippocampus tissue； its mechanism may be related to inhibiting the apoptosis of hippocampal neurons， increasing the level of neurotransmitters， the density of dendrite spines， preprotrusional proteins and the expressions of MAP-2 and BDNF proteins.