Linked Life Data

12668879

Source:http://linkedlifedata.com/resource/pubmed/id/12668879

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2003-4-1
pubmed:abstractText
The prolactin (PRL) deficit in mice homozygous for the spontaneous Ames dwarf (df) mutation coincides with a marked reduction in the number of PRL-regulating tuberoinfundibular dopaminergic (TIDA) neurons. The TIDA deficit develops after 14 21 d postnatally and may be prevented by PRL replacement initiated at 12, but not at 60, d of age. The present study was designed to define further the developmental period during which PRL can prevent the deficit in the number of TIDA neurons in df/df mice, as well as to evaluate whether exposure to PRL neonatally affects the response to PRL by TIDA neurons in later development. To address the first aim, litters of df/df and normal (DF/df) mice were treated daily with ovine PRL (50 microg intraperitoneally), starting at 12, 21, or 30 d of age. To address the second aim, DF/df and df/df animals treated with PRL for 30 d starting at 12 d of age were subjected to PRL withdrawal (15 d of saline vehicle treatment), followed by PRL retreatment. All brains were evaluated using both catecholamine histofluorescence and tyrosine hydroxylase (TH) immunocytochemistry. Total numbers of TH-immunostained cells were counted in area A12 (TIDA neurons) and in A13 (medial zona incerta). Qualitatively, catecholamine fluorescence in A12 perikarya and terminals in df/df mice was enhanced by PRL treatment initiated at 12 or 21, but not at 30, d of age. TH immunostaining intensity was enhanced in all df/df PRL-treated groups, compared with saline treatment. However, total numbers of TH-positive TIDA neurons were reduced significantly in df/df mice treated with PRL beginning at 21 or 30 d, as well as with saline at 12 d, compared with similarly treated DF/df groups and with df/df animals treated with PRL beginning at 12 d (p < 0.01 for all comparisons). Among dwarf mice treated with PRL beginning at 12 d, followed by PRL withdrawal, the numbers of TH-positive TIDA neurons were greater than those of saline-treated dwarfs, but less than those in DF/df mice (p < 0.05 for both comparisons). In dwarfs retreated with PRL after withdrawal, the TIDA population was also smaller than that in normal animals (p < 0.05), although it was larger than in vehicle-treated dwarfs of the same age (p < 0.05).
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
1355-008X
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
139-48
pubmed:dateRevised
2010-6-24
pubmed:meshHeading
pubmed:articleTitle
Prolactin replacement must be continuous and initiated prior to 21 d of age to maintain hypothalamic dopaminergic neurons in hypopituitary mice.
pubmed:affiliation
Department of Structural and Cellular Biology, Tulane University, New Orleans, LA 70112, USA. cjphelps@tulane.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.