Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:Q7LGC8 (HSD)
 3,196 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

By recording the incubation time needed for initial appearance of the red and blue formazans the reliability of the histochemical method for 3beta-HSD was investigated: 1. Prefixation of small tissue blocks with 1% W/V methanol-free formaldehyde (pH=7.2) for up to 30 min preserved morphological integrity as well as maximal enzyme activity. Moreover, the substantivity of formazans and lipids was enhanced. 2. Commercial available glutaraldehyde (pH=7.2) induced SH groups in the tissue (even at 0.1% W/V for 5 min) thereby enhancing the Nothing dehydrogenase reaction. 3. Preextraction of lipids with acetone for 20 min at -30 degree C caused no loss of activity and was an inevitable step if a reliable activity pattern had to be achieved (e.g. in interstitial cells). 4. No diffusion of enzyme was noticed within 30 min of preincubation in phosphate buffer (0.2 M, pH=7.2) at 20 degree C. 5. By using the double-section incubation method no diffusion of 3beta-HSD or rediffusion of NADH or PMSH could be noticed withn 45 min of incubation, provided that low concentrations of NAD (0.1 mg/ml) and PMS (0.003 mg/ml) were balanced against the concentration of Nitro BT (0.5 mg/ml) or Tetranitro BT (1.0mg/ml). 6. The utlity of different inhibitors of alkaline phosphomonoesterase was tested and discussed. 7. By inhibiting alkaline phosphomonoesterase with 0.1 mM of L-p-bromotetramisole or 16 mM of beta-glycerophosphate, 3beta-HSD was shown to be exclusively NAD-linked. 8. Levamisole was a potent inhibitor of NADH-tetrazolium reductase as well as 3 beta-HSD, but not of NADPH-tetrazolium reductase. 9. 3beta-HSD possess SH groups requisite for the activity as this enzyme was totally inhibited by N-ethyl maleimide. 10. Whether alcohol dehydrogenases may use steroids as substrate is discussed; It is concluded that preextraction (by acetone) and/or the use of an inhibitor of alcohol dehydrogenase (1,10-phenanthroline) has to be performed. 11. Propylene glycol was a poor solvent for all substrates and was itself an excellent substrate for alcohol dehydrogenase. 12. Specifications for the ideal solvent of steroid substrates in the histochemical practice are proposed. DMSO showed to be promising as a steroid solvent (e.g. extraction of formazans was considerably lower as compared to DMF). 13. The utilization of substrates was descending in the following order (using 1 mM and 0.1 ml/ml of either DMF or DMSO): epiandrosterone, methandriol, dehydroepiandrosterone and pregnenolone. 14. If DMSO was used as solvent for pregnenolone (but not for the other substrates tested) an evident increase of activity was recorded as compared to DMF.
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PMID:Histochemistry of 3beta-hydroxysteroid dehydrogenase in rat ovary. I. Amethodological study. 55 64

Aged (12- to 14-month-old) estrous and diestrous C57BL mice exhibited lower histochemically demonstrable ovarian delta5-3beta-hydroxysteroid dehydrogenase (3beta-HSD) activity in thecal, luteal, and interstitial cells, and lower (P less than 0.01) ovarian 3beta-HSD concentration and total content than did young (3-month-old) estrous animals. Administration of pregnant mare serum (PMS, 10 IU subcutaneously), followed in 40 hours by human chorionic gonadotropin (HCG, 5 IU subcutaneously) or HCG (2 IU daily for 4 days) alone, restored luteal and interstitial 3beta-HSD in aged mice. Follicular, lutea, and interstitial 3beta-HSD activity was increased in aged mice by a single PMS injection (10 IU). The total ovarian dehydrogenase concentration was increased 100% in aged animals by PMS and/or HCG administration. Restoration of histochemically demonstrable ovarian 3beta-HSD and total enzyme content in aged mice by PMS and/or HCG indicates ovarian sensitivity to gonadotropin and subnormal tropic hormone stimulation of the ovary in situ.
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PMID:Pregnant mare serum and human chorionic gonadotropin stimulate ovarian delta5-3beta-hydroxysteroid dehydrogenase in aged mice. 55 85

GnRH agonist and synthetic steroid such as Danazol, Medroxyprogesterone acetate (MPA) and Gestrinone are useful for the treatment of patients with endometriosis. These compounds induce atrophy and regression of endometriotic tissue, but the action mechanisms are still unclear. The present study, therefore, was undertaken to elucidate the mechanisms of these compounds in the treatment of endometriosis. In addition, a combination therapy with these compounds for endometriosis was also evaluated with an experimental animal model. Effects of GnRH agonist, Danazol and GnRH/Danazol combination on experimental endometriosis were evaluated in female rats. Endometrium autotransplanted under the renal capsule markedly decreased in size following castration. Histologic examination indicated atrophy and regression of the endometrial explant. The changes of endometrial explant were also induced by GnRH agonist, Danazol and combination treatment. However, a combination therapy with GnRH agonist and Danazol (93%) was shown to be superior to GnRH agonist (65%) and Danazol alone (45%) to induce atrophy and regression of experimental endometriosis. As expected, GnRH agonist significantly decreased serum E2, but Danazol did not at all. It is suggested that a combination therapy with GnRH agonist and Danazol may be a potential modality in the treatment of endometriosis. In order to evaluate whether Danazol, MPA, and Gestrinone has a direct inhibitory effect to synthesize estrogen, immature female rats were hypophysectomized and the ovaries were stimulated by a daily PMS injection. Administration of Danazol to the rats for two weeks stimulated the synthesis of 17, 20-lyase, 17 beta-HSD and aromatase activity, but did not inhibit any enzyme activities.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Studies on endocrine therapy of endometriosis]. 253 Feb 91

The steroid hormone has an important role in the early stages of reproduction. There has been abundant histochemical evidence that oocytes contain steroid hormones and are able to synthesize these hormones. But there have been few methods of analyzing one oocyte biochemically because it is too small and light. In order to study steroidogenesis in the oocyte, a microassay method sensitive enough to analyze the enzyme activities in one oocyte was developed using enzymatic cyling for amplifying the reaction product to 10,000-fold. An oil-well technique and a microtube method were applied in the assay for achieving the reaction in a medium as small as 1.0 to 5.0 microliters under a stereomicroscope. Immature Wistar rats were superovulated by PMS-hCG administration. Oocytes were collected by puncturing the follicle and flushing the tube. They were freeze-dried after washing to remove cumulus cells. The dry weight of one oocyte was 51.2 +/- 6.2 ng in a quartz fiber fishpole balance. The activity of 3 beta hydroxysteroid dehydrogenase (3 beta HSD) (picomol/oocyte/hr, substrate:pregnenolone) in the PMS-treated oocyte was 2.66 +/- 0.59, which corresponds to 3 times the activity of the ovarian homogenate as control, indicating the high capacity of oocytes to produce progesterone. The activity increased significantly (P less than 0.01) by hCG administration up to 4.17 +/- 0.29 after ovulation, suggesting that gonadotropin regulates steroidogenesis in the oocyte. The activities of G6PD and 6PGD were 8.41 +/- 1.09 picomol/oocyte/min and 3.85 +/- 2.02 picomol/oocyte/hr, respectively. The high activity of G6PD (more than 10 times that of the ovarian homogenate) suggests that the pentose phosphate shunt concerned with steroidogenesis is active in the oocyte. HCG decreased the activities of both G6PD and 6PGD. The present results show that steroidogenesis in the oocyte is very active under the control of gonadotropin, suggesting that steroid hormones may play an important role in oocyte maturation, ovulation and fertilization.
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PMID:[Studies on steroidogenesis in the oocyte]. 696 20