THE PHARMACOLOGICAL ACTIVITY OF 1-PHENYL-2-BUTYLAMINE

¹ Department of Pharmacology, West Virginia University School of Medicine, Morgantown, West Virginia

1-Phenyl-2-butylamine hydrochloride is about 1/275 as potent a vasopressor agent as epinephrine, and about 35 per cent as active as beta-phenethylamine and about 75 per cent as active as phenisopropylamine, or amphetamine, in barbitalized dogs. In 1 mgm./kgm. doses, 1-phenyl-2-butylamine has a duration of pressor effect that is about twice that of amphetamine, and seven times that of phenethylamine.

1-Phenyl-2-butylamine is most relaxant for isolated rabbit jejunum in concentrations of 100 mgm./l., phenisopropylamine next, and phenethylamine least relaxant, and often contractile in action. All three agents depress the function of the isolated perfused cat heart, and are ineffective against histamine spasm in perfused guinea pig lungs.

Twenty mgm. of phenisopropylamine hydrochloride per kgm. shortens the sleeping time of pentobarbitalized mice the most, with 1-phenyl-2-butylamine next, and phenethylamine inactive.

Oral doses as high as 6 mgm. of phenethylamine hydrochloride per kgm. had no demonstrable effect in man. As little as 0.25 mgm. of 1-phenyl-2-butylamine hydrochloride had some central nervous system stimulant effect, and 0.5 mgm./kgm. produced pronounced central nervous stimulant effects concomitant with a prolonged rise in blood pressure. One-fourth mgm. phenisopropylamine hydrochloride per kgm. produced a similar rise in blood pressure and central nervous system effects, although not so prolonged.