Hemoglobin damages the cultured endothelial cell monolayer from bovine cerebral arteries

We demonstrated that hemoglobin reaches the endothelial layers by an immunoelectron microscopic analysis in a rabbit subarachnoid hemorrhage model. Next, the effects of hemoglobin on cerebral artery endothelial cells were investigated both morphologically and histochemically using a cultured monolayer from a bovine endothelial cell system. The cultured monolayer was incubated with six different concentrations of hemoglobin ranging from 0 to 10(-5) M for 24 hrs on two-chambered glass slides. The denuded area of the glass slide increased dose dependently while the intensity of the actin fiber decreased. Superoxide dismutase did not modify this change. In a preliminary study, the endothelial cell membrane showed a hemoglobin binding molecule (94.5k dalton). This study thus suggests that the effects of hemoglobin on the endothelial monolayer were partly caused by the direct binding of hemoglobin to the membrane.