Preclinical pharmacological study on 125I-IPPA

Myocardial uptake of ¹²⁵I-IPPAin rats showed a peak of 4.4% of injected dose per gram.The half elimination time ofmyocardium was 3.8min and the maximaluptake of thyroid is only 0.005%ID/organ at 120min.The initial halftime of 2.7min in rabbits was obtained from the elimination curveofradioactivity in blood. In vitro binding test for ¹²⁵I-IPPA to HSAshowedrather constant level of activation during two hours.The second peak of extraction wasobserved in major organs ofrats, in rabbits' elimination of radioactivity and inbindingtest for ¹²⁵I-IPPA to albumin in vivo. Toxicity trial was up tostandard.The tolerance of a mouse to IPPA was 560 times as highas that of a person to IPPA. Itdemonstrated that ¹²⁵I-IPPA couldbe quickly extracted by myocardium, and itscatabolites were excretedin the urine with almost no iodine loss. All the results werefound toagree with the expectations based on the principal metabolic path ofphenyl fattyacid.