In vivo and in vitro 99mTc-protein bound of renal agents: 99mTc-prylidinomethyltetracycline (99mTc-Sn-Pmt) and 99mTc-Sn-Gluco-ene-diolate (99mTc-Gluco)

Protein binding affects tissue distribution, plasma clearance and uptake of renal radiopharmaceuticals. The ^99mTc bound to plasma protein after incubation ^99mTc-Gluco-ene-diolate (^99mTc-Sn-Gluco) agent or ^99mTc-prylidinomethyl-tetracycline (^99mTc-Sn-PMT) agent with plasma protein. It was observed that the protein bound to ^99mTc is lesser extent with (^99mTc-Sn-Gluco) agent than with the ^99mTc-PMT agent. ^99mTc-Sn-PMT is excreted more rapidly than ^99mTc-Sn-Gluco. On the other hand the percentage binding to protein seems to depend on the origin of the protein and or the type of protein (human or animal). However lower human protein binding or higher protein binding were observed with ^99mTc-Sn-Gluco or with ^99mTc-Sn-PMT, respectively compared with the binding to rat protein. The unbroken down of the chemical form of the origin of these two agents and the highest of ^99mTc-Sn-Gluco remained as origin in urine indicate that ^99mTc-Sn-Gluco are more stable than ^99mTc-Sn-PMT.Concerning the type of protein binding to ^99mTc-Sn-PMT or to ^99mTc-Sn-Gluco, it was observed that Human Plasma Protein is greater binding than Human serum protein or than IgG.