Recent studies suggest certain Epithelial Na⁺ Channel (ENaC) proteins may be components of mechanosensitive ion channel complexes in vascular smooth muscle cells that contribute to pressure-induced constriction in middle cerebral arteries (MCA). However, the role of a specific ENaC protein, ENaC, in pressure-induced constriction of MCAs has not been determined. The goal of this study was to determine if pressure-induced constriction in the MCA is altered in a mouse model with reduced levels of ENaC. Using quantitative immunofluorescence, we found whole cell ENaC labeling in cerebral VSMCs was suppressed 46% in ENaC homozygous mutant (m/m) mice compared to wildtype littermates (+/+). MCAs from ENaC +/+ and m/m mice were isolated and placed in a vessel chamber for myographic analysis. Arteries from ENaC +/+ mice constricted to stepwise increases in perfusion pressure and developed maximal tone of 10 ± 2% at 90 mm Hg (n=5). In contrast, MCAs from ENaC m/m mice developed significantly less tone (4 ± 1% at 90 mm Hg, n=5). Vasoconstrictor responses to KCl (4-80 mM) were identical between genotypes and responses to phenylephrine (10^-7-10^-4 M) were marginally altered suggesting reduced levels of VSMC ENaC specifically inhibit pressure-induced constriction. Our findings indicate ENaC is required for normal pressure-induced constriction in the MCA and provide further support for the hypothesis that ENaC proteins are components of a mechanosensor in VSMCs.