AIM: To investigate the effects of calcitonin gene-related peptide (CGRP) on cultured anoxic-reoxygenation human umbilical vein endothelial cells. METHODS:In the present experiment, an anoxic-reoxygenation model was established by using cultured human umbilical vein endothelial cells. The uptake rate of trypan-blue and calcium and magnesium contents of endothelial cells and lactic dehydrogenase (LDH) activity in medium and malondialdhyde (MDA) content of endothelial cells were measured 60,120 and 180 min after anoxia and 30 and 60 min after reoxygenation, and the effects of 1?10 -8 mol/L CGRP on anoxic-reoxygenation endothelial cells were studied. RESULTS: The findings showed that, as anoxia prolonged, the uptake rate of trypan-blue and LDH activity and MDA content gradually elevated and, during reoxygenation, these parameters sharply increased. Calcium and magnesium levels gradually declined as anoxia prolonged, and during reoxygenation calcium content significantly increased. Meanwhile, 1?10 -8 mol/L CGRP might significantly reduce the uptake rate of trypan-blue and LDH activity and MDA content during anoxia and reoxygenation and lessen the increase in calcium content and the loss of magnesium during reoxygenation. CONCLUSION: These results showed that CGRP might have a direct protective function to endothelial cells afflicted with anoxic-reoxygenation injury by inhibiting lipid peroxidation, attenuating calcium overload and loss of magnesium and enzyme.