Abstract:
:Allopregnanolone is a neuroactive steroid synthesized in rat gonads, adrenal cortex, and central nervous system. It has been suggested that sex steroid hormones might influence allopregnanolone concentrations but no clear data have ever been reported. The aim of the present study was to investigate the effects of administration of 17beta-estradiol (17beta-E2), the raloxifene analog LY-117018 or their combination on allopregnanolone levels in fertile and ovariectomized (OVX) rats. Thirteen groups of 12 Wistar female rats each received either 17beta-E2 (0.1 or 1 microg/day) or LY-117018 (25, 250, and 1,250 microg/day), or 17beta-E2 1 microg/day plus LY-117018: 25, 250, and 1,250 microg/day for 14 days. The rats were then sacrificed and allopregnanolone content was assessed in the hypothalamus, hippocampus, pituitary, adrenals, and serum. Ovariectomy determined a significant decrease in allopregnanolone content in the hypothalamus, hippocampus, pituitary, and serum, while increasing it in the adrenals (p<0.01). In OVX rats, the administration of either 17beta-E2 or LY- 117018 restored ovariectomy-induced allopregnanolone changes. The administration of LY-117018 in addition to 17beta-E2 to OVX animals suppressed the increase in allopregnanolone levels determined by 17beta-E2 in the hippocampus, hypothalamus, and pituitary, but not in the adrenals and serum. In fertile rats, the administration of LY-117018 reproduced the effects of ovariectomy. This study shows that the raloxifene analog LY-117018 has an estrogen-like action on the central nervous system of OVX rats when administered alone, while it acts as an antiestrogen in the presence of 17beta-E2, both in OVX animals treated with 17beta-E2 and in fertile rats. A different effect was observed in the adrenal glands. The mechanism of action of this compound has still to be clarified.
journal_name
Neuroendocrinologyjournal_title
Neuroendocrinologyauthors
Genazzani AR,Bernardi F,Stomati M,Monteleone P,Luisi S,Rubino S,Farzati A,Casarosa E,Luisi M,Petraglia Fdoi
10.1159/000054583subject
Has Abstractpub_date
2000-09-01 00:00:00pages
162-70issue
3eissn
0028-3835issn
1423-0194pii
54583journal_volume
72pub_type
杂志文章abstract::The rise in the concentration of LH in the serum that takes place in ovariectomized, estrogen-primed rats exposed to the odors from a cage with bedding soiled by a male rat was completely prevented by bilateral lesions destroying the ventral premammillary (PMv) nuclei. These results suggest that the pheromonal stimuli...
journal_title:Neuroendocrinology
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journal_title:Neuroendocrinology
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doi:10.1159/000124668
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journal_title:Neuroendocrinology
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doi:10.1159/000126633
更新日期:1994-01-01 00:00:00
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pub_type: 临床试验,杂志文章,随机对照试验
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doi:10.1159/000127113
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124844
更新日期:1987-10-01 00:00:00
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更新日期:1989-05-01 00:00:00
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doi:10.1159/000126257
更新日期:1992-09-01 00:00:00
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更新日期:1994-02-01 00:00:00
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pub_type: 杂志文章
doi:10.1159/000123594
更新日期:1983-12-01 00:00:00
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更新日期:1995-02-01 00:00:00
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更新日期:1987-11-01 00:00:00
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更新日期:1981-02-01 00:00:00
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pub_type: 杂志文章
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更新日期:1988-03-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000124871
更新日期:1987-12-01 00:00:00
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journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000126372
更新日期:1993-01-01 00:00:00
abstract::Substance P (SP) is known to act on pituitary hormone release either at the hypothalamic level or directly at the pituitary level. In order to investigate whether SP is present in the pituitary gland and to localize the peptide at the cellular and subcellular levels, the immunocytological method was used. Rat pituitar...
journal_title:Neuroendocrinology
pub_type: 杂志文章
doi:10.1159/000123360
更新日期:1982-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:1986-01-01 00:00:00
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pub_type: 杂志文章
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更新日期:2002-11-01 00:00:00
abstract::To further investigate the role of serotonin in human prolactin (Prl) secretion, serotonin antagonists have been administered to healthy volunteers in basal conditions and after pretreatment with the selective blocker of dopamine receptors, pimozide (Pim). Highly significant falls (p less than 0.001) in serum Prl were...
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pub_type: 临床试验,杂志文章
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