Leucocytes and Thrombosis

Abstract
White cell loss from a rotating flask system is enhanced by noradrenaline, adrenaline, isoprenaline, 5HT and tendon extracts. Noradrenaline is the most active agent in this test of white cell behaviour and unlike the other materials its action is not blocked by an ADP-removing system. Adenosine inhibits both platelet loss and white cell loss, but concentrations can be found which selectively block the former. The implications of these findings for our understanding of the mechanism of polymorphonuclear leucocyte involvement in thrombus formation are discussed, but the role of white cells once they have become involved in thrombus formation has not yet been determined.