the d-isomer was only approximately 1/8th as potent as the l-isomer for inhibiting isoproterenol tachycardia , and the lowest dose of the d-isomer coadministered with quinidine produced antiarrhythmic potentiation but little if any inhibition of isoproterenol tachycardia .
C0022245
isoproterenol
C0039231
tachycardia