Linked Life Data

9364809

Source:http://linkedlifedata.com/resource/pubmed/id/9364809

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1997-12-9
pubmed:abstractText
Growth hormone acts directly on liver cells; it binds to its receptor and induces a multitude of intracellular events leading, for example, to the production of insulin-like growth factor-1 (IGF-1). While much is known about the biochemical side of these events, their structural correlates are less well examined. Here, we examined livers of transgenic mice (TM) expressing human GH, in an attempt to correlate at the cellular level the site of GH gene expression with effects on morphology and mitotic behavior of liver cells within the hepatic architecture. Using in situ hybridization histochemistry we observed a striking expression pattern of the hGH gene in hepatocytes near the periportal spaces. In the same regions, the hGH protein, but no IGF-1 immunoreactive product, was detected using immunohistochemical methods. In the sections of TM livers, 6.8-31.9% of cells were hGH-immunoreactive. However, the cellular hGH staining pattern was not homogeneously distributed in the immunoreactive cells. Two main patterns became obvious. In the majority of the immunoreactive cells a cytoplasmic stain was present. These cells exhibited normal liver cell features and were not enlarged (type I). In the other group (type II), the staining was stronger and concentrated, sometimes punctuate, and often confined to cytoplasmic compartments which were in a perinuclear position. The latter staining pattern was generally seen in morphologically altered cells, which were enlarged and possessed intranuclear inclusions and invaginations. In the the periportal regions, mitotically active hepatocytes were evident, but these cells, as judged from immunocytochemistry, apparently did not express the transgene. In conclusion, different staining patterns for hGH may indicate different levels of transgene expression, which could be associated with difficulties in the cells with regard processing and/or secreting the hormone. In addition to the endocrine actions implied by the high hGH levels in the peripheral circulation of these TM, intracrine actions are also suggested (type II staining pattern), but para- and autocrine loops are possible as well (type I staining pattern). Whether IGF-1 is involved, and the mechanism underlying hepatocyte cell proliferation, remain to be examined.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0040-8166
pubmed:author
pubmed:issnType
Print
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
611-6
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1997
pubmed:articleTitle
Visualizing the expression of a human growth hormone (hGH) transgene in the liver: intrahepatic regional and intracellular differences of expression are associated with morphological alterations and hepatocellular proliferation.
pubmed:affiliation
Abteilung Anatomie, Universität Ulm, Ulm/Donau, Germany.
pubmed:publicationType
Journal Article, Comparative Study