111In-labelled baboon platelets: the influence of in vivo redistribution and contaminating 114mIn on the radiation dose.

In five normal baboons, whole body 111In decreased slowly (t1/2 = 60 days) after the end of platelet lifespan. There was slight elution of radioactivity from the liver and spleen, the important sites of platelet sequestration. A fraction of this eluted radioactivity accumulated in the bone marrow, but also in other tissues. This redistribution did not have a significant effect on the measurement of in vivo platelet kinetics. It did however, diminish the total weighted radiation dose, especially that due to contaminating 114mIn.

A comparison of the acute hemodynamic effects of nifedipine and nisoldipine in patients with ischemic reduced left ventricular function.

Nisoldipine (BAY k 5552) like nifedipine, is a dihidropyridine compound with strong calcium blocking activity. The purpose of this study was to measure and compare the absolute hemodynamic effects of these two drugs before and at 30 min, 60 min and 120 min after oral intake in 20 ischemic heart disease patients with radionuclide gated cardiac scintigraphy. No significant change was seen in end diastolic volume index with either of the drugs. With nifedipine the stroke volume index (SVI) increased significantly from the basal value at 30 min (P = 0.004) and 60 min (P = 0.034) yet not significantly at 120 min. The same trend was seen in left ventricular ejection fraction (LVEF) with significant increases at 30 min (P = 0.02) and 60 min (P = 0.025) yet not at 120 min. The cardiac index increased significantly at 30 min (P = 0.001), 60 min (P = 0.002) and 120 min (P = 0.025) but the latter value was significantly lower than the 30 min value indicating the maximal effect had already passed. With nisoldipine the SVI increased significantly at 60 min (P = 0.004) and 120 min (P = 0.001) but not at 30 min. These changes were again reflected by a significant increase in LVEF at 60 min (P = 0.021) and 120 min (P = 0.002) without significant increase at 30 min. The increase in CI was highly significant at 60 min (P = 0.003) and 120 min (P = 0.001) without significant change at 30 min. Nisoldipine proved to be a potent calcium antagonist with slower onset and longer duration of action than nifedipine.