PERIPHERAL AND CARDIAC EFFECTS OF A NEW PHOSPHODIESTERASE INHIBITOR IN COMPARISON WITH ENOXIMONE

The effect of the new phosphodiesterse inhibitor R80122 (E) cyclohexyl -N-methyl-2-[[[phenyl(1,2,3,5-tetrahydro -2-oxoimidazo[2,1-b]-quinazol in-7-yl)methylene] amino]oxy]acetamide, (CAS 133718-29-3) on haemo-dyn amic parameters and myocardial oxygen consumption were intraindividual ly compared with those of enoximone, a clinically established phosphod iesterase inhibitor. In 12 anaesthetised sheep the drugs were given in randomized order as i. v. infusions for 6 min at each setting (10, 20 and 30 mu g.kg(-1).min(-1) (R80122) and 32, 64 and 96 mu g.kg(-1).min (-1) (enoximone)). R 80122 as well as enoximone caused a significant i ncrease in cardiac inotropism with a simultaneous increase of myocardi al oxygen consumption. The peripheral resistance was significantly dec reased by both drugs. The haemodynamic effects elicited by the applica tion of equieffective doses of RS0122 and enoximone did not show any d ifferences.