Dietary cholesterol protects against alcohol-induced cerebral artery constriction (AICAC) in absence of complex neuronal integrity and factors from systemic blood circulation. Diameter traces from isolated, in vitro pressurized middle cerebral artery of rats on control (A) vs. high-cholesterol (B) diet. Isolated arterial segments (1–2 mm long) possessed an intact, functional endothelium. However, they were deprived of physiologically active circulating factors. (C) Averaged data showing similar degree of KCl-induced constriction in cerebral arteries from rats on control vs. high-cholesterol diet. (D) Averaged data showing similar degree of myogenic tone in cerebral arteries from rats on control vs. high-cholesterol diet. (E) Averaged data showing protective effect of dietary cholesterol against AICAC when evaluated in isolated arterial segments. In (C-E), each point represents the average of ≥5 arteries, each artery harvested from a different rat. *p<0.05, when compared to arteries from rats on control diet.