Bis-N-nitroso-caged nitric oxides: photochemistry and biological performance test by rat aorta vasorelaxation.
Three new caged nitric oxides (NOs)-BNN3, BNN5Na, and BNN5M were tested for biological use. BNNs have a strong ultraviolet (UV) absorption band (lambda(max): 300 nm, epsilon: 13.5 mM(-1) cm (-1)) extended to 420 nm and produce NO upon irradiation with 300-360 nm light in quantum yields about 2. A photoexcited BNN molecule yields two NOs with time constants of less than 10 ns for phase 1 and less than 20 micros for phase 2 at 37 degrees C, suggesting usefulness of BNNs for measuring in vivo and in vitro fast NO reactions. Upon irradiating with UV light, caged nitric oxides-loaded rat aortic strips maintained in a state of active tonic contraction effectively relaxed ( < 3 microM BNN5M loading solution concentration). BNN3 is incorporated in the lipid membrane. BNN5Na, insoluble in organic solvents but water soluble, localizes in the water phase. BNN5M, is muscle-cell-permeable and hydrolysed to BNN5Na to remain in cytosol. BNNs were thermally stable and demonstrated no observable toxicity.
Namiki
S
S
Department of Chemistry, University of Tsukuba, Ibaraki, Japan.
Kaneda
F
F
Ikegami
M
M
Arai
T
T
Fujimori
K
K
Asada
S
S
Hama
H
H
Kasuya
Y
Y
Goto
K
K
D000818:Animals; D001011:Aorta / Q000502:physiology*; D002478:Cells, Cultured; D006868:Hydrolysis; D066298:In Vitro Techniques; D008297:Male; D009569:Nitric Oxide / Q000737:chemistry* / Q000502:physiology; D010777:Photochemistry; D051381:Rats; D017208:Rats, Wistar; D013056:Spectrophotometry, Ultraviolet; D014664:Vasodilation / Q000502:physiology*
D009569:Nitric Oxide