Thrombin-induced alterations in endothelial cell cytoarchitectural and functional properties.

alpha-Thrombin interacts with confluent bovine pulmonary artery endothelial cells to produce two types of actin microfilament rearrangements: (1) The loss of cortical actin correlates with interruption of barrier integrity, evident from increased permeability to 125I-albumin; and (2) an increase in actin stress fibers results in greater adherence of the cells to their extracellular substrate. Use of phallatoxin compounds that stabilize actin filaments and prevent their depolymerization prevents both the cytoarchitectural and functional changes resulting from thrombin challenge.