Linked Life Data

11399792

Source:http://linkedlifedata.com/resource/pubmed/id/11399792

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-6-11
pubmed:abstractText
These experiments tested whether in utero and lactational exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) alters mammary gland differentiation, estrogen receptor alpha (ERalpha) expression levels, or the response to estrogen in the female postpubertal rat mammary gland. Pregnant Holtzman rats were administered a single oral dose of 1 microg/kg TCDD or vehicle on gestation-day 15. Exposed and non-exposed female offspring were weaned on postnatal day 21 and ovariectomized at 9 weeks of age. Two weeks later, both TCDD and control animals were divided into 3 groups, receiving treatment with placebo, 0.025, or 0.1 mg 17beta-estradiol pellet implants. After 48 h, mammary tissue was removed for analysis following euthanasia. TCDD-exposed mammary glands demonstrated impaired differentiation as measured by the distribution of terminal ductal structures and increased expression levels of ERalpha. The response to exogenous estrogen was tested in TCDD-exposed animals and compared to control non-exposed animals. Estrogen stimulation of the TCDD-exposed glands induced progesterone receptor expression and mammary gland differentiation as measured by a shift in distribution from terminal end buds and terminal ducts to Types I and II lobules. Control glands were better differentiated at baseline and did not exhibit any significant changes in the distribution of terminal ductal structures following estrogen stimulation. The increase in progesterone receptor-expression levels by exogenous estrogen in control glands was similar to the TCDD-exposed glands. These experiments demonstrate that in utero and lactational exposures to TCDD impair mammary gland differentiation but that TCDD-exposed mammary glands retain the ability to differentiate in response to estrogen.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
1096-6080
pubmed:author
pubmed:issnType
Print
pubmed:volume
62
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
46-53
pubmed:dateRevised
2010-9-17
pubmed:meshHeading
pubmed-meshheading:11399792-Actins, pubmed-meshheading:11399792-Animals, pubmed-meshheading:11399792-Animals, Newborn, pubmed-meshheading:11399792-Breast, pubmed-meshheading:11399792-Cell Differentiation, pubmed-meshheading:11399792-DNA Primers, pubmed-meshheading:11399792-Estrogen Antagonists, pubmed-meshheading:11399792-Estrogen Receptor alpha, pubmed-meshheading:11399792-Estrogens, pubmed-meshheading:11399792-Female, pubmed-meshheading:11399792-Immunoenzyme Techniques, pubmed-meshheading:11399792-Ki-67 Antigen, pubmed-meshheading:11399792-Lactation, pubmed-meshheading:11399792-Ovariectomy, pubmed-meshheading:11399792-Pregnancy, pubmed-meshheading:11399792-Prenatal Exposure Delayed Effects, pubmed-meshheading:11399792-RNA, Messenger, pubmed-meshheading:11399792-Rats, pubmed-meshheading:11399792-Rats, Sprague-Dawley, pubmed-meshheading:11399792-Receptors, Estrogen, pubmed-meshheading:11399792-Receptors, Progesterone, pubmed-meshheading:11399792-Reverse Transcriptase Polymerase Chain Reaction, pubmed-meshheading:11399792-Tetrachlorodibenzodioxin
pubmed:year
2001
pubmed:articleTitle
In utero and lactational treatment with 2,3,7,8-tetrachlorodibenzo-p-dioxin impairs mammary gland differentiation but does not block the response to exogenous estrogen in the postpubertal female rat.
pubmed:affiliation
Institute of Human Virology, Division of Infectious Diseases, Department of Medicine, University of Maryland Medical School, Baltimore Maryland 21201, USA.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't