Tamolarizine (Tamolarizine free base) free base is a novel calcium antagonist.

Tamolarizine (0.1-10 microM) synergistically potentiated the cytotoxicity of doxorubicin for doxorubicin-resistant K562 cells (K562/DXR), but had hardly any synergistic effects in the parental cell line (K562) at the same concentration. Moreover, tamolarizine inhibits the P-glycoprotein pump-efflux activity in a dose-related manner and reduces the expression of the immunoreactive P-glycoprotein in K562/DXR cells as evaluated by cytofluorimetric assay.[1]

Tamolarizine (40 mg/kg; rats; immediately after 15-min brain ischemia) showed slight impairment of place learning during the course of this test, they later reached almost the same performance level as the sham-operated group. Selective neuronal loss in the CA1 subfield was much less in the ischemia+tamolarizine group than in the ischemia+saline group. These results indicate that tamolarizine treatment protects the hippocampus from ischemic brain damage and ameliorates place learning impairment.[2]