Amelioration of Vasospasm After Subarachnoid Hemorrhage in Transgenic Mice Overexpressing CuZn–Superoxide Dismutase

Abstract
Background and Purpose—To clarify the effect of superoxide dismutase (SOD) on vasospasm after subarachnoid hemorrhage (SAH), we investigated sequential changes in arterial diameter after SAH in transgenic mice overexpressing CuZn-SOD (SOD-1). Methods—SOD-transgenic mice and nontransgenic littermates (35 to 40 g) were subjected to SAH produced by endovascular perforation of left anterior cerebral artery. At 4 hours and 1, 3, 7, and 14 days after SAH, the mice were perfused with 10% formalin and consequently with a mixture of carbon black and 10% gelatin to cast all vessels. Vasospasm was evaluated by measuring the diameter of the left middle cerebral artery (MCA) with a microscope. Results—In nontransgenic mice, the diameter of the MCA on day 3 after SAH (110.5±20.5 μm [mean±SD]; n=16) was significantly reduced compared with that without SAH (138.5±14.5 μm; n=12) (P<0.01). Moreover, on day 3 after SAH, the diameter of the MCA in SOD-transgenic mice (127.9±20.2 μm; n=20) was significantly larger than that i...