Early accumulation of the terminal complement-complex in the ischaemic myocardium after reperfusion.
The terminal, membrane-damaging complement complex C5b-9 accumulates in the infarcted myocardium. In experimental myocardial infarction, we investigated the time course of C5b-9 deposition and the influence of reperfusion. In a group of 17 rabbits (group 1), the circumflex coronary artery was occluded for different time periods ranging from 0.5 to 29 h without subsequent reperfusion. A second group of 23 rabbits (group 2) underwent coronary artery occlusion for periods ranging from 0.5 to 6 h followed by reperfusion. C5b-9 was determined in transmural myocardial biopsies by immunohistochemistry and by ELISA. In group 1, C5b-9 accumulation in the ischaemic myocardium was found only after 5 to 6 h of coronary artery occlusion. In group 2 (ischaemia and reperfusion), significant C5b-9 deposition was already observed after 30 min of myocardial ischaemia. We conclude that in the absence of reperfusion C5b-9 accumulation occurs as a late event when most of the jeopardized myocardium has probably already become necrotic. In the presence of reperfusion, however, the complement system is activated rapidly and this could play a role in the pathogenesis of reperfusion injury.
Department of Cardiology, University Hospital Eppendorf, Hamburg, Germany.
D
D
Mathey
J
J
Schofer
H J
HJ
Schäfer
T
T
Hamdoch
H C
HC
Joachim
A
A
Ritgen
F
F
Hugo
S
S
Bhakdi
D000818:Animals; D015938:Complement Membrane Attack Complex / Q000032:analysis* / Q000502:physiology; D004797:Enzyme-Linked Immunosorbent Assay; D007150:Immunohistochemistry; D009203:Myocardial Infarction / Q000378:metabolism*; D015425:Myocardial Reperfusion; D015428:Myocardial Reperfusion Injury / Q000209:etiology; D009206:Myocardium / Q000378:metabolism*; D011817:Rabbits; D013997:Time Factors
D015938:Complement Membrane Attack Complex