Hormone Replacement Therapy: Pros and Cons...Natural Alternatives

There are two estrogen receptor types...alpha and beta, and there may be others. Alpha receptors are located in the target cell nucleus. Binding affinity to these receptors determines biological activity, but is not the only factor involved. The particular way that chemicals bind to a receptor site may be affected by other chemicals that have preferential affinities for the site. Thus, a single compound may have different activities on each of the receptors.