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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: BACKGROUND, METHODS, RESULTS. Meshes: Animals, Cell Division, Gene Deletion, Hepatectomy, Liver, Liver Regeneration, Mice, Mice, Knockout, Microcirculation, Neovascularization, Physiologic, Organ Size, Plasminogen, Urokinase-Type Plasminogen Activator.
user
Does plasminogen mediate liver regeneration and angiogenesis after experimental partial hepatectomy? Context: Plasmin system components are upregulated after partial hepatectomy, but their contribution to surgery-induced hepatic angiogenesis and regeneration is unclear. Liver regeneration and angiogenesis after partial hepatectomy were examined in mice lacking plasminogen or urokinase plasminogen activator (uPA). Mice with a single-gene deletion of plasminogen or uPA were subjected to 70 per cent partial hepatectomy. Liver regeneration was measured as relative liver weight and cell proliferation index. Angiogenesis was quantified by determining hepatic microvessel density after staining for sinusoidal endothelial cells. The liver remnant weight was significantly reduced in mice lacking plasminogen or uPA compared with that in wild-type mice on days 2 and 7 after partial hepatectomy. This correlated with impaired cell proliferation. In wild-type mice, regeneration was accompanied by a significant increase in microvessel density after hepatectomy; this increase was impaired in plasminogen-deficient mice.
assistant
Plasminogen and uPA are essential for optimal liver regeneration. In addition, plasminogen appears to be a major determinant in regeneration-associated hepatic angiogenesis. Final Decision: yes