[Interaction of sex steroids with proteins from the soluble fraction of swine and cattle liver (a preliminary analysis)].
The interactions of [3H]estradiol, [3H]testosterone and [3H]progesterone with soluble proteins from porcine and calf liver were studied. The specific binding of [3H]progesterone and [3H]testosterone in calf liver cytosol seems to be due to serum transcortin or its intracellular precursor (analog). Contrariwise, the specific binding of [3H]progesterone observed in porcine liver cytosol was absent in the serum. This binding was characterized by slow association and dissociation dynamics, moderate affinity for the [3H]-ligand and a high binding capacity. The structural determinants of the ligands were studied by competitive inhibition of the [3H]-ligand binding. The delta 4-3-keto group in the steroid A-ring was found to be the most important determinant. An intensive metabolism of [3H]progesterone was observed during its incubation with cytosol (data from thin-layer chromatography). A 3H-metabolite (presumably, 20 beta-dihydroprogesterone) was predominant in the bound ligand fraction. The data obtained suggest that proteins of a steromodulin type are widely distributed in the mammalian liver.
Smirnov
A N
AN
Zhavoronkov
S N
SN
D000818:Animals; D001667:Binding, Competitive; D002417:Cattle; D002855:Chromatography, Thin Layer; D003600:Cytosol / Q000378:metabolism; D004958:Estradiol / Q000378:metabolism*; D005260:Female; D008099:Liver / Q000378:metabolism*; D008297:Male; D011374:Progesterone / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism*; D013552:Swine; D013739:Testosterone / Q000378:metabolism*
D011506:Proteins; D013739:Testosterone; D011374:Progesterone; D004958:Estradiol
Vzaimodeĭstvie polovykh steroidov s belkami rastvorimoĭ fraktsii pecheni svin'i i korovy (predvaritel'nyĭ analiz).