This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Pathology
[{'content': 'Immediate sustained permeability in cells is increased by: \nSelect and explain. \nA. Direct injury and necrosis, B. Endothelial gaps by histamine, C. Endothelial gaps by serotonin, D. Leucocyte mediated endothelial injury', 'role': 'user'}, {'content': 'Answer: A \nExplanation: Direct endothelial injury, resulting in endothelial cell necrosis and detachment:\n\nThis effect is usually encountered in necrotizing injury, and is due to direct damage to the endothelium by the injurious stimulus e.g. In severe burns or lytic lesions.\nNeutrophils adhere to the endothelium, and may also injure\xa0the endothelium.\nIn most instances, leakage starts immediately after the injury and is sustained at a high level for several hours, until the damaged vessels are thrombosed or repaired.\nThis reaction is immediate sustained response. All levels of microcirculation are affected, including venules, capillaries, and arterioles.\nEndothelial cell detachment is often associated with platelet adhesion and thrombosis.', 'role': 'assistant'}]