Catecholamine-associated smooth muscle contraction bands in the media of coronary arteries of brain-dead baboons.

In the brain death baboon model, the baboon experiences an autonomic storm with release of catecholamines both from the adrenal glands and from intracardiac sympathetic nerve endings. Since catecholamines may induce coronary arterial spasm, we looked for morphologic evidence of smooth muscle damage in the coronary arteries of 11 baboons that underwent induction of brain death under general anesthesia. Nine (82%) of the 11 animals showed coronary arterial smooth muscle contraction bands, and 9 (82%) of the 11 baboons also showed focal myocardial contraction bands and myocytolytic necrosis. Focal coronary arterial smooth muscle cell necrosis with intracytoplasmic calcium deposits were observed in three (33%) of the nine contraction band-positive cases. This study provides further support for the concept that medial smooth muscle contraction bands may be a morphologic marker of antemortem coronary arterial spasm.