Enzyme Activity in Kidney, Adrenal and Gonadal Tissue of Rats Treated Neonatally With Androgen or Oestrogen

Ghraf, Rüdiger; Hoff, Hanns-Georg; Lax, E. R.; Schriefers, Herbert

doi:10.1677/joe.0.0670317

Cited by 21 publications

(5 citation statements)

References 18 publications

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“…However, the response of polycystic ovaries in androgen-sterilized rats to acute LH injections, in terms of the secretion of these two metabolites, remained small in spite of an increase in progesterone secretion (groups 2 vs 4). This indicates that 5a-reductase activity in follicular polycystic ovaries was lower than that in normal pre¬ ovulatory ovaries, as has been observed in vitro by Ghraf, Hoff & Schriefers (1975).…”

Section: Discussionsupporting

confidence: 53%

Effects of multiple injections of LH on the secretion of pregnane compounds from polycystic ovaries of androgen-sterilized rats

Sawada¹

1986

Journal of Endocrinology

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Differences in the secretion of pregnane compounds by follicular polycystic ovaries of androgen-sterilized rats and by normal preovulatory ovaries of early pro-oestrous rats were compared. Some rats were injected i.v. with LH 30 min before bleeding, in order to stimulate the secretion of steroids. This injection of LH greatly increased the secretion of progesterone, 5 alpha-pregnane-3,20-dione and 3 alpha-hydroxy-5 alpha-pregnan-20-one by both types of ovaries. The response of the two progesterone metabolites in the polycystic ovaries was low, suggesting low 5 alpha-reductase activity. Because it is known that the preovulatory LH surge is absent in androgen-sterilized rats, a classical approach was taken to circumvent the probable deficit in cyclic release of LH by giving an i.v. injection of LH (25 micrograms) every 4 days for 16 days. Ovarian venous blood was collected 4 days after the last injection. The mean secretion of 5 alpha-pregnane-3,20-dione and 3 alpha-hydroxy-5 alpha-pregnan-20-one from the ovaries of such androgen-sterilized rats became much (P less than 0.01) higher than that of multiple saline-treated controls. These results suggest that low 5 alpha-reductase activity of polycystic ovaries in androgen-sterilized rats may be due to the absence of cyclic release of LH from the pituitary gland.

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Section: Discussionsupporting

confidence: 53%

Effects of multiple injections of LH on the secretion of pregnane compounds from polycystic ovaries of androgen-sterilized rats

Sawada¹

1986

Journal of Endocrinology

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“…This indicates that the 5a-reductase activity in polycystic ovaries is lower than in ovaries with normal follicles, as has been observed in vitro by Ghraf et al (1975). The secretion of 5ct-pregnane-3,20-dione and 3a-hydroxy-5cx-pregnan-20-one is significantly higher in ovaries with follicles than in those with¬ out (Sawada & Ichikawa 1978).…”

Section: Discussionmentioning

confidence: 70%

Effects of multiple injections of luteinizing hormone on secretion of pregnane compounds from polycystic ovaries of rats exposed to constant light

Sawada

Kosaka²,

Ichikawa³

1987

Acta Endocrinologica

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Differences in the secretion of pregnane compounds by ovaries with cystic follicles of rats exposed to constant light (light-induced oestrous rats) and by ovaries with normal follicles of early pro-oestrous rats were studied. Some rats were injected iv with 2 \ g=m\ g of LH to stimulate the secretion of steroids 30 min before their blood was sampled. The injection greatly increased the secretion of progesterone by both kinds of ovaries. The secretion of 5\g=a\-pregnane-3,20-dione and 3\g=a\-hydroxy-5\g=a\-pregnan-20-one also increased in normal rats, but not in the polycystic ovaries of l i ght \ x=req-\ induced oestrous rats, which suggested that the 5\ g=a\ \ x=r eq-\ reductase activity was low. The pre-ovulatory LH surge is absent in light-induced oestrous rats, so a classic approach was taken to circumvent the probable deficit in the cyclic release of LH; we gave multiple injections of 10 \g=m\g of LH. Five such injections were given at intervals of 4 days, and ovarian venous blood was collected 4 days after the last injection. Cystic follicles in the ovaries of rats disappeared when the injections of LH were given every 4 days. The production of 5\g=a\-pregnane-3,20-dione and 3\g=a\-hydroxy-5\g=a\-pregnan\x=req-\ 20-one from the ovaries of such rats was significantly higher (P < 0.01) than in controls given multiple injections of saline. These results suggest that the low 5\g=a\-reductase activity in polycystic ovaries of l i ght \ x=req-\ induced oestrous rats may be due to the absence of an LH surge from the pituitary gland.Patterns in the secretion of progesterone, 5ct-pregnane-3,20-dione, 3a-hydroxy-5ct-pregnan-20-one, 20a-hydroxy-4-pregnen-3-one, 20a-hydroxy-5a-pregnan-3-one, and 5a-pregnane-3a,20a-diol have been found in the ovarian venous plasma of rats during the oestrous cycle (Ichikawa et al. 1974).The first three steroids listed promptly increase after an injection of LH (Ichikawa et al. 1972, 1974, which suggests that LH stimulates not only progesterone biosynthesis but also its metabolism in the rat ovary. Both 5a-pregnane-3,20-dione and 3a-hydroxy-5a-pregnan-20-one help regu¬ late FSH and LH secretion in immature female rats primed with pregnant mare's serum gona¬ dotropin and kept under constant light (Murphy

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“…Glira/ e t al. [9] observed that neo natal androgenization had no effect on adult adrenal 5a-reductase, whereas estrogenization caused an increase in the enzyme. In contradistinction to these results, Goldman et al [10] reported a lowering of 5a-reductase by neonatal androgenization.…”

Section: Discussionmentioning

confidence: 97%

Uptake and Retention of Sex Steroids by the Neonatal Rat Adrenal Gland

Je¹,

Pt²,

Ej³

1982

Neonatology

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The uptake of radioactivity in the adrenal glands of 5-day-old male and female rats was examined 2 h following injection of radiolabeled testosterone, R1881, diethylstilbestrol, or estradiol. The adrenals of both sexes had higher levels of radioactivity than blood after testosterone or synthetic androgen (R1881) injection. The adrenals of neither sex showed any significant accumulation of radioactivity, following ³H-estradiol injection. When, however, cytosol prepared from neonatal adrenal glands was incubated with 2 nM ³H-estradiol, and the incubate subjected to column chromatography on Sephadex G-100, radioactivity was eluted with the void volume; this peak was absent with the addition of 100-fold unlabeled estradiol to the incubation. The possible role of α-fetoprotein in preventing the in vivo uptake and retention of 17β-estradiol is discussed since ³H-diethylstilbestrol, an estrogen which has low affinity for this protein, was retained by the adrenals of male rats. It is concluded that estrogens or androgens can have a direct effect on the neonatal adrenal gland.

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Enzyme Activity in Kidney, Adrenal and Gonadal Tissue of Rats Treated Neonatally With Androgen or Oestrogen

Cited by 21 publications

References 18 publications

Effects of multiple injections of LH on the secretion of pregnane compounds from polycystic ovaries of androgen-sterilized rats

Effects of multiple injections of LH on the secretion of pregnane compounds from polycystic ovaries of androgen-sterilized rats

Effects of multiple injections of luteinizing hormone on secretion of pregnane compounds from polycystic ovaries of rats exposed to constant light

Uptake and Retention of Sex Steroids by the Neonatal Rat Adrenal Gland

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