Analysis of vasodilatory action of a new nitroester agent, 2-nicotinamidoethyl nitrate (SG-75).
Effects of 2-nicotinamidoethyl nitrate (SG-75) on cardiovascular system were investigated using whole animals and isolated vascular smooth muscles of dogs and rabbits. In dogs in vivo SG-75 i.v. produced dose-dependent falls in systemic blood pressure (SBP) concomitant with increases in heart rate (HR). Hypotension by SG-75 was not affected by propranolol and atropine but slightly inhibited by diphenhydramine. Norepinephrine (NE) dose-dependently increased SBP, and SG-75 could not affect these effects of NE. In dog coronary arterial strips contracted with potassium, SG-75 produced a dose-dependent relaxation of these strips. These effects of SG-75 were not affected by propranolol and atropine, but slightly inhibited by diphenhydramine. NE dose-dependently increased the tension of helical strips prepared from rabbit femoral artery, rabbit aorta and dog coronary artery. But SG-75 could not alter these effects of NE. The results suggest that SG-75 may have not an adrenergic beta-receptor stimulating action, a muscarinic action and an adrenergic alpha-receptor blocking action, but an inconsiderable histamine-like action. Probably, a main action of SG-75 may be a nitroglycerin-like action.
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D004285:Dogs; D004347:Drug Interactions; D006339:Heart Rate / Q000187:drug effects; D006439:Hemodynamics / Q000187:drug effects*; D066298:In Vitro Techniques; D009130:Muscle, Smooth / Q000187:drug effects; D009200:Myocardial Contraction / Q000187:drug effects; D009536:Niacinamide / Q000031:analogs & derivatives* / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D013997:Time Factors; D014665:Vasodilator Agents
D009566:Nitrates; D014665:Vasodilator Agents; D009536:Niacinamide; D009638:Norepinephrine