Positive reference sera showed RPP values between 9.3% and 103.3%.
Negative reference sera from the Philippines showed RPP values between −7.3% and 27.2%.
The RPP-adjusted values were calculated as follows: [stress/rest MBFi]/[stress/rest RPP] = [stress MBFi/RPP]/[rest MBFi/RPP] and reported as sympathetic-stress myocardial flow reserve (sMFR).
Treatment of hearts with either isoproterenol or adenosine alone improved haemodynamic function recovery after 30 min global ischaemia and 60 min reperfusion (Table 3 ); the recovered LVDP and RPP reached twice the values of control reperfused hearts.
Decrease of RPP correlated with initial RPP as well as with decrease of BMI, and of diastolic BP.
After RPP adjustment, the NE control values of sMFR in the normal mice were equal to the low-dose SB values (1.4-fold increase), reflecting a similar level of endothelium-dependent (and NO-mediated) stimulation.
In our study cardiac recovery was defined as the presence of a spontaneous heartbeat accompanied by a regular heart rhythm with a RPP > 10% of the baseline value for more than 1 minute.
Four treatments were control, low-RPP (LRPP), medium-RPP (MRPP) and high-RPP (HRPP) with 0, 0.48, 0.48 and 0.64 g RPP per kg dietary DM, respectively.
When hearts perfused with isoproterenol were switched to adenosine, RPP was reduced to 60% of the initial value (P < 0.01) and was significantly lower than in adenosine-treated hearts (P < 0.01).
To account for changes in baseline MBF caused by cardiac workload, baseline MBF values were corrected for the rate pressure product (RPP), an index of myocardial oxygen consumption [ 24], by multiplying baseline MBF by the mean RPP in the patients as a group, divided by the RPP in the individual patient [ 25].
The mean values of the relative changes in [PCr] and RPP carried out experimentally for the determinations of the elasticities are presented in table 2. Interestingly, the increase in balloon pressure induced a lower decrease in [PCr] (−8.9% vs −13.5%) for a higher increase in RPP (+20.0% vs +15.5%) in CH hearts when compared with Controls (table 2).
