Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:1.12.7.2 (hydrogenase)
 3,522 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A crude human hypophyseal extract (HE), as well as human growth hormone (GH), ovine prolactin (PRL) and commercial preparations of ACTH, TSH, pregnant mare's serum gonadotrophins (PMS) and chorionic gonadotrophin (CG) were tested for their ability to induce the activities of cytoplasmic 17 beta-hydroxysteroid dehydrogenase and microsomal delta 4-5alpha-hydrogenase and to repress the activities of microsomal 3alpha- and 3beta-hydroxysteroid dehydrogenases in the liver of hypophysectomized rats. The activity of 17beta-hydroxysteroid dehydrogenase was not affected by any of the administered hormones. For the other enzymes, only PRL was effective in causing changes in the activities; the repressive effect on 3alpha-hydroxysteroid dehydrogenase activity was highly significant (P less than 0.001). These results indicate that PRL is involved in the regulation of at least some of the enzyme activities of hepatic steroid hormone metabolism.
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PMID:Regulation of the activities of the enzymes involved in the metabolism of steroid hormones in rat liver: the effect of administration of anterior hypophyseal hormones and gonadotrophin preparations to hypophysectomized rats. 18 36

Previous studies have established that the effects of estradiol (E2) on hepatic steroid and drug metabolism are demonstrable only in the presence of the pituitary gland. Studies were carried out to test the hypothesis that GH is the pituitary feminizing factor mediating the actions of E2 on hepatic metabolism. E2 and GH administered to castrated male rats had similar effects on hepatic enzymes, decreasing the oxidataive metabolism of drugs [ethylmorphine demethylation, aniline, hydroxylation, and benzo(a)pyrene hydroxylation) and increasing steroid (corticosterone) delta 4-hydrogenase activity. None of these effects of E2 or GH could be demonstrated in hypophysectomized (hypox) rats. However, GH administration to T4- or ACTH-treated hypox rats resulted in some of the changes in drug and steroid metabolism seen in animals with intact pituitary glands. The actions of GH on hepatic microsomal enzymes were fully demonstrable in hypox rats receiving both T4 and ACTH. E2 had no effects in T4 plus ACTH-treated hypox rats. These and prior observations are consistent with the hypothesis that GH mediates the actions of E2 on hepatic microsomal drug- and steroid-metabolizing enzymes. The data also indicates that the cations of GH on hepatic metabolism are dependent upon the interactions with still other endocrine factors.
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PMID:Is growth hormone the pituitary feminizing factor mediating the actions of estradiol on hepatic drug and steroid metabolism? 677 28