GLUCOCORTICOID ACTIVITY OF VARIOUS PROGESTERONE ANALOGS: CORRELATION BETWEEN SPECIFIC BINDING IN THYMUS AND LIVER AND BIOLOGIC ACTIVITY

摘要: When tested in an vitro assay system, progesterone and various analogs of this steroid were shown to compete with [3H] triamcinolone acetonide (TA) for specific glucocorticoid receptors both rat liver thymus. Of these analogs, the following derivatives potent competitors TA binding and, when injected into adrenalectomized rats, induced regression thymus marked increases hepatic tyrosine aminotransferase activity: 11 beta-hydroxyl, 6 alpha-methyl, alpha, 16 alpha-dimethyl, alpha-methyl-17 alpha-hydroxyl. In contrast, progesterone, 17 alpha-hydroxy competed but failed elicit either gluco- or antiglucocorticoid activity vivo. Also, we observed that oral contraceptive alpha-methyl-17-(1-propynyl)testosterone competes very effectively a cell-free preparation induces increase activity. The beta-hydroxyl group has previously been thought be essential Our studies indicate substitution testosterone alpha-methyl negates need substitutuent as prerequisite