Platelet Production Rate Determination with (75Se)-Seleno-Methionine

Platelet production rate measurements can be a useful tool for monitoring thrombopoietic factors. Currently available techniques suffer from a number of drawbacks and we have made an attempt to develop a method which is sufficiently direct to avoid cumbersome empirical corrections; its accuracy and reproducibility have been adjusted so as to obtain a final procedure simple enough for routine use. The isotope incorporation technique is a method currently used for production rate measurements. A loading of a suitable precursor is given (usually by injection) and after an appropriate period of time the amount of radioactivity (RA) incorporated is measured. The production rate is often expressed as the percentage ratio between the label incorporated and the injected dose (1,2) as given by relation 1: $$\frac{{RA in the peripheral platelets}}{{RA injected}} \times 100$$