Aortic cross-clamping influences regional net release and uptake rates of tissue-type plasminogen activator in pigs
1997 (English)In: Acta Anaesthesiol Scand, Vol. 41, no 9, 1114-23 p.Article in journal (Refereed) Published
BACKGROUND: The key regulator of intravascular fibrinolysis, tissue-type plasminogen activator (t-PA), is released from a dynamic endothelial storage pool. The aim of the study was to investigate regional t-PA net release and uptake rates in response to infra-renal aortic cross-clamping (AXC) and declamping (DC). METHODS: Anesthetized pigs were studied during 5 min of AXC, followed by a 35-min declamping (DC) period. Arterio-venous concentration gradients of total and active t-PA, as well as respective plasma flows, were simultaneously obtained across the preportal, hepatic, coronary and pulmonary vascular beds. Plasma levels of total t-PA (ELISA with purified porcine t-PA as standard), and active t-PA (spectrophotometric functional assay) were determined. RESULTS: Prior to AXC, we found a high net release rate of total t-PA across the preportal vascular bed (1700 ng.min-1 P < 0.001), and a high hepatic net uptake (4900 ng.min-1, P < 0.001), while coronary and pulmonary t-PA net fluxes were small and variable. AXC per se did not induce significant alterations in net fluxes of t-PA. Following DC, preportal and coronary net releases of total t-PA increased (to 2900 ng.min-1 and 60 ng.min-1, respectively). Despite an increase in hepatic net uptake of total t-PA (to 6100 ng.min-1) after DC, a significant increase in hepatic venous total t-PA occurred. CONCLUSIONS: The release and uptake of t-PA is indicated to be dynamic and organ-specific. DC induces an acute profibrinolytic reaction in preportal organs. The high hepatic t-PA uptake capacity restricts preportal profibrinolytic events to affect the systemic circulation.
Place, publisher, year, edition, pages
1997. Vol. 41, no 9, 1114-23 p.
*Anesthesia, Animals, Constriction, Coronary Circulation, Endothelium, Vascular/metabolism, Hemodynamics, Liver Circulation, Pulmonary Circulation, Regional Blood Flow/physiology, Swine, Time Factors, Tissue Plasminogen Activator/*blood
Anesthesiology and Intensive Care
IdentifiersURN: urn:nbn:se:umu:diva-66525ISBN: 0001-5172 (Print)OAI: oai:DiVA.org:umu-66525DiVA: diva2:607301
Seeman-Lodding, H Haggmark, S Jern, C Jern, S Johansson, G Winso, O Biber, B Research Support, Non-U.S. Gov't Denmark Acta anaesthesiologica Scandinavica Acta Anaesthesiol Scand. 1997 Oct;41(9):1114-23.2013-02-222013-02-222015-09-15