In vivo and in vitro ^99mTc-protein bound of renalagents: ^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.