administration of isoproterenol in doses that increased heart rate from 69 +/- 9 to 99 +/- 12 beats/min produced a decrease in diastolic time from 485 +/- 98 to 312 +/- 47 msec and only a slight decrease in percent diastole , from 54.2 +/- 4.3 % to 50.6 +/- 3.9 % .
C0022245
isoproterenol
C0039231
increased heart rate