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Binding of toremifene to human serum proteins
Pharmacology & Toxicology
|July 1, 1988
Summary
Toremifene highly binds to human serum proteins, with 99.7% protein-bound. This binding is primarily to albumin (92%), indicating significant drug-protein interaction in vivo.
Area of Science:
- Pharmacology
- Biochemistry
Background:
- Toremifene is a selective estrogen receptor modulator (SERM) used in cancer therapy.
- Understanding drug-protein binding is crucial for predicting pharmacokinetics and efficacy.
Purpose of the Study:
- To quantify the in vitro protein binding of toremifene in human serum.
- To identify the specific serum proteins to which toremifene binds.
Main Methods:
- Radioactive labeling (3H-toremifene) and ultracentrifugation were used to measure protein binding.
- Agarose gel electrophoresis was employed to fractionate serum proteins.
- Radioactivity localization and protein visualization identified binding sites.
Main Results:
- Toremifene exhibited high protein binding (99.7%) in human serum, independent of drug concentration.
- The majority of bound toremifene was associated with albumin (92%).
- Minor binding occurred with beta 1 globulin (6%) and alpha 1 acid glycoprotein (2%).
Conclusions:
- Toremifene demonstrates extensive binding to serum proteins in vitro.
- Albumin is the primary binding protein for toremifene in human serum.
- These findings are important for understanding toremifene's distribution and disposition.
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