Aging-related alterations in eNOS and nNOS responsiveness and smooth muscle reactivity of murine basilar arteries are modulated by apocynin and phosphorylation of myosin phosphatase targeting subunit-1.

ABSTRACT: Aging causes major alterations of all components of the neurovascular unit and compromises brain blood supply. Here, we tested how aging affects vascular reactivity in basilar arteries from young (<10 weeks; y-BA), old (>22 months; o-BA) and old (>22 months) heterozygous MYPT1-T-696A/+ knock-in mice. In isometrically mounted o-BA, media thickness was increased by ∼10% while the passive length tension relations were not altered. Endothelial denudation or pan-NOS inhibition (100 µmol/L L-NAME) increased the basal tone by 11% in y-BA and 23% in o-BA, while inhibition of nNOS (1 µmol/L L-NPA) induced ∼10% increase in both ages. eNOS expression was ∼2-fold higher in o-BA. In o-BA, U46619-induced force was augmented (pEC₅₀ ∼6.9 vs. pEC₅₀ ∼6.5) while responsiveness to DEA-NO

SUBMITTER: Lubomirov LT 

PROVIDER: S-EPMC5363478 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature