
Bronchodilator and Cardiovascular Effects of NKH477, a Novel Water-Soluble Forskolin Derivative, in Guinea Pigs
Author(s) -
Masashi Iida,
Norifumi Fujita,
Makoto Hosono,
Yoshikazu Sukenaga
Publication year - 1995
Publication title -
japanese journal of pharmacology/japanese journal of pharmacology
Language(s) - English
Resource type - Journals
eISSN - 1347-3506
pISSN - 0021-5198
DOI - 10.1254/jjp.68.245
Subject(s) - forskolin , guinea pig , bronchodilator , derivative (finance) , pharmacology , chemistry , medicine , business , receptor , finance , asthma
The bronchodilator and cardiovascular effects of NKH477 (6-(3-dimethylaminopropionyl)forskolin hydrochloride) were evaluated. In anesthetized guinea pigs, i.v. bolus injections of NKH477 (1-100 micrograms/kg) inhibited the bronchoconstriction induced by inhaled leukotriene D4, increased the heart rate (HR) and decreased the diastolic arterial blood pressure (DBP) in a dose-dependent manner. The bronchodilator effect of NKH477 was 1500 times more potent than that of aminophylline and 17 times less potent than that of isoproterenol. The selectivity of NKH477 for bronchodilation vs an increase in HR was 15 times higher than that of isoproterenol and similar to that of aminophylline; and vs a decrease in DBP, the selectivity was 4 times higher than that of aminophylline and similar to that of isoproterenol. I.v. infusion of NKH477 (0.1-3 micrograms/kg/min) for 2 hr dose-dependently inhibited the bronchoconstriction induced by i.v. histamine. Isoproterenol (0.1 microgram/kg/min, i.v.) enhanced the bronchoconstriction after termination of the infusion, whereas NKH477 did not. In conscious guinea pigs, inhalation of NKH477 (0.1-5 mg/ml) concentration-dependently inhibited the bronchoconstriction induced by inhaled histamine, and a high concentration of NKH477 (35.4 mg/ml) increased the HR. The bronchodilator effect of inhaled NKH477 was 15 times less potent than that of isoproterenol. The selectivity of inhaled NKH477 was similar to that of isoproterenol. These results indicate that NKH477 may be useful as a bronchodilator.