Toxic oxygen metabolites and ischemia-reperfusion increase histamine synthesis and release in the isolated rat heart.
Histamine is synthetized in the heart, and released by ischemia-reperfusion injury in several species. Histamine has arrhythmogenic, chronotropic, inotropic and vasoactive effects. Cardiac histamine release during ischemia-reperfusion may be mediated by toxic oxygen metabolites. We studied the effect of ischemia-reperfusion and toxic oxygen metabolites on release and synthesis of histamine in the isolated rat heart (Langendorff model). The following groups were included: I, (n = 10) control perfusion for 60 min; II, (n = 7) H2O2 (200 microM) was given for 10 min followed by 50 min recovery; III, (n = 7) thiourea (15 mM) was given in addition to H2O2; IV, (n = 7) thiourea given alone; V, (n = 7) catalase (150 U/ml) plus H2O2; VI, (n = 7) 20 min ischemia followed by 40 min reperfusion. The contents of histamine in the coronary effluent and in cardiac tissue were measured repeatedly (radioenzymatic method). Ischemia-reperfusion and toxic oxygen metabolites increased release of histamine in the coronary effluent. Concomitantly the histamine contents in cardiac tissue increased, indicating increased synthesis of histamine.
Valen
G
G
Department of Surgery and Anesthesiology, University of Tromsø, Norway.
Kaszaki
J
J
Szabó
I
I
Nagy
S
S
Vaage
J
J
D000818:Animals; D003326:Coronary Circulation / Q000502:physiology; D006339:Heart Rate / Q000502:physiology; D006632:Histamine / Q000096:biosynthesis* / Q000378:metabolism; D066298:In Vitro Techniques; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism* / Q000633:toxicity; D011312:Pressure; D051381:Rats; D017208:Rats, Wistar; D016276:Ventricular Function
D006632:Histamine; D010100:Oxygen