Identification of nitric oxide synthases in isolated bovine brain vessels.
We have studied the presence of neuronal nitric oxide synthase (nNOS) and endothelial nitric oxide synthase (eNOS) in parenchymal and pial bovine cerebral vessels by using western blot analysis. The different vessel structures were analysed by microscopic observation and their biochemical features determined by using gamma-glutamiltranspeptidase (gamma-GTP) as an endothelial marker and alpha-smooth muscle actin (alpha-SMA) as a smooth muscle cell marker. nNOS could not be found in parenchymal vessels, being present only in pial vessels; eNOS was present in all vessel-fractions studied, albeit a different distribution was found. Thus, the eNOS is more abundant in the parenchymal vessels which are associated with smooth muscle cells whereas both pial vessels and brain microvessels, almost devoid of actin, show extremely low levels. Two main conclusions can be obtained: first, nNOS is exclusively restricted to pial vessels and, second, eNOS is present in endothelial cells which are in association with smooth muscle cells.
Catalán
R E
RE
Departamento de Biología Molecular, Centro de Biología Molecular Severo Ochoa (CSIC-UAM), Universidad Autónoma de Madrid, Spain.
Martínez
A M
AM
Aragonés
M D
MD
Hernández
F
F
D000818:Animals; D015153:Blotting, Western; D001921:Brain / Q000098:blood supply; D002417:Cattle; D002536:Cerebral Arteries / Q000201:enzymology*; D004730:Endothelium, Vascular / Q000201:enzymology*; D008833:Microcirculation; D019001:Nitric Oxide Synthase / Q000032:analysis*
D019001:Nitric Oxide Synthase