Linked Life Data

8404616

Source:http://linkedlifedata.com/resource/pubmed/id/8404616

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1993-11-3
pubmed:abstractText
Changes in the concentration of transforming growth factor-alpha (TGF alpha) protein were measured in regenerating liver. TGF alpha stimulates both DNA and protein synthesis in various liver-derived cells, and its mRNA levels increase in liver after partial hepatectomy (PH), suggesting that it may be an important autocrine regulator of liver regeneration. Using a sheep antiserum raised against mature rat TGF alpha, we developed a sensitive TGF alpha RIA. TGF alpha was extracted from livers in a detergent-containing buffer with protease inhibitors. Liver extracts, to a volume of 10 microliters/tube, produced a displacement curve of [125I]TGF alpha that was parallel to the pure standard. The TGF alpha content of normal liver was 57.04 +/- 26.25 pg/mg protein, 5.24 +/- 2.61 ng/mg DNA, and 10.33 +/- 4.47 ng/g liver (n = 5; mean +/- SD). Between 13-17 h after operation, TGF alpha concentrations in the livers of PH animals increased over those in sham-operated (SH) controls (P < 0.05) and remained twice those in SH controls for more than 96 h, returning to control values by 8 days. In unoperated liver, gel chromatography showed all TGF alpha immunoactivity to be in fractions corresponding to known TGF alpha precursors (15-30 kilodaltons). Mature 5.6-kilodalton TGF alpha was not detected until 48 h after PH and was still present at 96 h. These data support a role for TGF alpha in the response to PH in the rat. However, the presence of TGF alpha precursors in normal liver, the short (< 4-h) interval between the increase in TGF alpha concentrations and the onset of hepatocyte DNA synthesis, the sustained elevation of TGF alpha levels after DNA synthesis has ceased, and the lack of detectable processing to the mature form until DNA synthesis has subsided all suggest that the membrane-anchored precursor and the mature forms of TGF alpha may have different functions, cellular sources, or target cells in regenerating liver.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0013-7227
pubmed:author
pubmed:issnType
Print
pubmed:volume
133
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1731-8
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Transforming growth factor-alpha (TGF alpha) concentrations increase in regenerating rat liver: evidence for a delayed accumulation of mature TGF alpha.
pubmed:affiliation
Department of Pediatrics, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2579.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.