Premium
EFFECTS OF NITRO‐l‐ARGININE ON ENDOTHELIUM‐DEPENDENT RELAXATION OF CANINE CEREBRAL ARTERIES
Author(s) -
Ohta Fumihito,
Kobayashi Yuta,
Shinozuka Kazumasa,
Shimoura Keiko,
Hattori Keisuke,
Moritake Kouzo
Publication year - 1993
Publication title -
clinical and experimental pharmacology and physiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.752
H-Index - 103
eISSN - 1440-1681
pISSN - 0305-1870
DOI - 10.1111/j.1440-1681.1993.tb01718.x
Subject(s) - basilar artery , cerebral arteries , mole , chemistry , middle cerebral artery , arginine , relaxation (psychology) , vasodilation , prostaglandin , endocrinology , medicine , biochemistry , amino acid , ischemia
SUMMARY 1. The effect of N G ‐nitro‐l‐arginine (NO 2 Arg) on the relaxation of canine basilar artery was investigated and compared with those of middle cerebral and femoral arteries. 2. NO 2 Arg (10 −7 ‐3 × 10 −5 mol/L) inhibited the substance‐P (Sub‐P; 10 −12 ‐10 −8 mol/L) induced relaxation in the basilar artery precontracted with prostaglandin F 2α (PGF 2α ; 10 −5 mol/L) or KCl (10 −2 mol/L) in a concentration‐dependent manner and a ratio of the maximum inhibition by NO 2 Arg (3 × 10 −5 mol/L) was more than 90%. 3. The relaxation induced by A23187 (10 −9 ‐3 × 10 −6 ) was also abolished by NO 2 Arg (3 × 10 −5 mol/L), but that by glyceryl trinitrate (GTN; 10 −9 ‐3 × 10 −5 mol/L) was not, in the basilar artery precontracted with PGF 2α (10 −5 mol/L). N G ‐nitro‐d‐arginine (NO 2 ArgD; 3 × 10 −5 mol/L) did not affect the relaxation induced by Sub‐P (10 −12 ‐10 −8 mol/L). 4. l‐arginine (l‐Arg; 3 × 10 −5 ‐10 −4 mol/L) did not inhibit Sub‐P (10 −12 ‐10 −8 mol/L) induced relaxation in the basilar artery. Pretreatment of l‐Arg (10 −4 mol/L) reversed the relaxation inhibited by NO 2 Arg (3 × 10 −6 mol/L) in the arteries. 5. NO 2 Arg (3 × 10 −5 mol/L) inhibited the Sub‐P (10 −12 ‐10 −8 mol/L) induced relaxation in the canine middle cerebral artery as much as in the basilar artery. NO 2 Arg (3 × 10 −5 mol/L) also inhibited Sub‐P (10 −12 ‐10 −8 mol/L) induced relaxation in the femoral artery, but the degree of the inhibition was less than that in the basilar artery. 6. These results suggest that the endothelium‐derived relaxing factor (EDRF) of canine basilar artery is mainly l‐Arg derived nitric oxide which may play a more important role in the basilar artery than the femoral artery.