ABSTRACT
Previous work in our laboratory has defined two estrogen binders in male rat liver cytosol, one a putative estrogen receptor found in both sexes, and the other a species unique to the male. We tested other tissues of male rats by gel filtration chromatography and estrogen binding studies to detect whether similar protein speus work in our laboratory has defined two estrogen binders in male rat liver cytosol, one a putative estrogen receptor found in both sexes, and the other a species unique to the male. We tested other tissues of male rats by gel filtration chromatography and estrogen binding studies to detect whether similar protein speus work in our laboratory has defined two estrogen binders in male rat liver cytosol, one a putative estrogen receptor found in both sexes, and the other a species unique to the male. We tested other tissues of male rats by gel filtration chromatography and estrogen binding studies to detect whether similar protein species were present. Several of the tissues assayed contained a high affinity receptor-like molecule: pancreas greater than liver greater than kidney greater than lung greater than testes greater than scrotal skin. This species could not be detected in spleen, jejunum, and epididymis. The same tissues were also assayed to detect the male-specific estrogen binding protein. This protein was undetectable in any other tissues examined and appears to be specific for liver tissue. Because of this tissue specificity, we have postulated a role for it as a mechanism for binding and possibly eliminating excess estrogen in the male.