Tpc1808 is a candidate chemotropic factor induced by nerve injury, and we report here the role of rat Tpc1808 in the expression of high-molecular-weight neurofilament (NF-H) in PC12 cells. A full-length Tpc1808 cDNA encoding the 275-amino-acid protein was constructed into pcDNA-HA and transfected into PC12 cells. The increased expression of NF-H was detectable in PC12-Tpc1808 clones by semi-qRT-PCR, real-time PCR, Western blot, and immunofluorescence. Such an increase could also be observed in PC12 cells subjected to recombinant Tpc1808 protein by real-time PCR and immunohistochemistry. At a concentration of 0.1 microg/mL, Tpc1808 protein, similar to NGF, could promote the expression of NF-H in a time-dependent manner. Our findings suggest that Tpc1808 is the gene related to promotion of nerve growth, and both the Tpc1808 gene and the Tpc1808 recombinant protein up-regulate the expression of NF-H in PC12 cells.