Abstract: Objective To observe the morphological variation of seminiferous tubules and the expressions of the androgen receptor(AR) and tyrosine kinase receptor c-kit in the testicular tissue in formaldehyde exposure SD rats after being treated with compound panax notoginseng(CPN). Methods Eighteen male SD rats were randomly divided into three groups：control，formaldehyde and CPN group．Formaldehyde and CPN group were stayed in the chambers filled with formaldehyde vapor（69.5±8.3ppm）for 8 weeks（8hours/day）. From the fifth week, the rats in CPN group were treated with CPN(1ml/100g) everyday for 4 weeks. At the end of the experiment, the whole body and testes of all rats were weighed. The seminiferous tubules and the expressions of androgen receptor and c-kit in testicular tissues observed with HE staining and the immunohistochemical method,respectively. Results The weights of bodies and testes in the formaldehyde group decreased significantly in comparison with the control group.After treated with CPN for 4 weeks, both weights significantly increased compared to the formaldehyde group(EM>P/EM><0.05). The atrophy of the convoluted seminiferous tubules，disorderly arrangement, enlarged interval of epithelial cells of the tubules and the remarkable loss of the sperms were observed in the formaldehyde group using HE staining. The morphology of seminiferous tubules gradually recovered, and lots of spermatids appeared in the seminiferous tubules in CPN group.The expressions of androgen receptor and c-kit in testicular tissues decreased significantly in formaldehyde group, but increased remarkably almost to the normal level in CPN group(EM>P/EM><0.05). Conclusion Formaldehyde exposure for a long time causes the loss of the weights of bodies and testes and the declines of the expressions of androg

Key words: Compound panax notoginseng, Formaldehyde, Testis, Androgen receptor, Oncogene protein c-kit, Immunohistochemistry, Rat