Abstract:
:Increasing concentrations of estradiol (E2) ranging from 0.01 to 10 nM were found to inhibit partially but significantly the lactogenic effect of ovine prolactin (oPRL) on alpha-lactalbumin production in primate mammary tissues maintained in organ culture for 9 days. E2 at 10 nM inhibited by 38% (mean) PRL-stimulated alpha-lactalbumin production measured by radioimmunoassay. E2 antagonized the effect of oPRL by reducing new alpha-lactalbumin synthesis as determined by specific immunoprecipitation of alpha-lactalbumin and by analysis with NaDodSO4 gel electrophoresis. In immunoprecipitation studies, the mean inhibition of alpha-lactalbumin production was 57.6%. E2 in the absence of oPRL had no effect on alpha-lactalbumin production. In contrast to previous observations in rodents, progesterone was found to be a much weaker inhibitor of PRL-induced alpha-lactalbumin production than was E2 in primate breast tissues. Mean inhibition of oPRL-stimulated alpha-lactalbumin production was 32.3% with 10 microM progesterone and 8.3% with 10 nM. The inhibitory effect of E2 on oPRL-stimulated alpha-lactalbumin production was significantly reversed by both tamoxifen and a new antiestrogen, LY 156758. Although exact comparison of the effects of these two antiestrogens was not possible, it was apparent that LY 156758 was more potent in blocking the E2 inhibitory effect. In summary, these studies provide evidence that physiologic concentrations of estradiol partially block the lactogenic effect of PRL in primate mammary glands, suggesting a new role for estrogen in mammary physiology. The inhibitory effect of estrogen treatment on milk production in women after parturition may possibly be explained by this direct antagonism between E2 and PRL.
journal_name
Proc Natl Acad Sci U S Aauthors
Kleinberg DL,Todd J,Babitsky Gdoi
10.1073/pnas.80.13.4144subject
Has Abstractpub_date
1983-07-01 00:00:00pages
4144-8issue
13eissn
0027-8424issn
1091-6490journal_volume
80pub_type
杂志文章abstract::Humans are consciously aware of some memories and can make verbal reports about these memories. Other memories cannot be brought to consciousness, even though they influence behavior. This conspicuous difference in access to memories is central in taxonomies of human memory systems but has been difficult to document i...
journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
doi:10.1073/pnas.071600998
更新日期:2001-04-24 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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doi:10.1073/pnas.75.12.6243
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1974-06-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1996-12-24 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1993-11-15 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2004-08-10 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:1979-11-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:1978-10-01 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2016-07-12 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
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更新日期:2005-06-14 00:00:00
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journal_title:Proceedings of the National Academy of Sciences of the United States of America
pub_type: 杂志文章
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更新日期:2014-01-21 00:00:00