Peculiarities of adriamycin cardiotoxicity in spontaneously hypertensive rats (SHR)

The adriamycin (ARD) effects on the myocardium and the microcirculatory system (m.s.) of the heart and the skeletal muscle were studied enzyme histochemically and histomorphometrically. Normotensive Wistar rats (ADR-NWR) and SHR (ADR-SHR) were given 3 weekly intravenous injections of 1 mg ADR/kg b.wt. Controls were injected with saline. Besides the well-known ADR-induced single-cell degeneration observed in both strains, ADR-SHR have developed focal myocardial lesions (f.m.l.) to be characterized as ischemic alterations. Their number and size have distinctly increased as compared to saline-treated SHR. In the coronary m.s. the ADR applications were followed by signs of structural adaptation to chronic contractions, especially in ADR-SHR and within the f.m.l. The latter were considered to be decisively engendered by the pathological reactions of the m.s. In ADR-SHR possible the cardiotoxic ADR actions have aggravated these microvessel reactions and their consequences.