Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0432222 (SEM)
 47,337 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Using antisera directed towards the C-terminal region of gastrin releasing peptide (GRP), significant quantities of GRP-like immunoreactivity (GRPLI) were detected in ovine amniotic fluid and in the fetal and maternal circulations. The highest GRPLI levels were found in amniotic fluid (2135 +/- 829 fmol/ml, n = 12; mean +/- SEM), followed by those in ovine fetal (604 +/- 267 fmol/ml, n = 13) and maternal plasma (229 +/- 89 fmol/ml, n = 13). On gel filtration chromatography, the predominant GRPLI form in each fluid eluted in an identical position consistent with the entity being of apparently larger molecular size than porcine GRP1-27. Certain fetal plasma samples contained a second GRPLI peak eluting at the void volume. Hence, during ovine pregnancy a GRPLI entity circulates in fetal and maternal plasma; the entity is of apparently larger molecular size than GRP1-27 but contains a structure immunologically indistinguishable from the bioactive c-terminal region of GRP1-27. Given the recognized bioactivities of GRP, this entity may be an important hormone during ovine fetal life.
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PMID:Gastrin releasing peptide immunoreactivity is present in ovine amniotic fluid and fetal and maternal circulations. MRC Group in Fetal and Neonatal Health and Development. 139 47

Gastrin-releasing polypeptide (GRP) has been implicated in the development of the human fetal lung. To determine whether GRP has a wider role in fetal development, its actions on DNA synthesis and cell replication by isolated epiphyseal growth plate chondrocytes obtained from ovine fetuses between 35 days gestation and near term (145 days) were examined. Chondrocytes were isolated using collagenase from the proximal tibia and cultured in monolayer. Synthesis of DNA was assessed from the incorporation of [3H]thymidine into previously growth-restricted cells after incubation in medium supplemented with GRP1-27 (40-1280 nM). Increase in cell number was assessed after incubation with test medium for 1 week. GRP caused a dose-dependent increase in both cell number and DNA synthetic rate compared to control incubations. Cell number was increased by 50% in the presence of a maximally effective 160 nM GRP and DNA synthesis by up to 800% utilizing chondrocytes obtained from animals of 75-80 days gestation. The mean (+/- SEM) half-maximal concentration of GRP for the stimulation of DNA synthesis was 97 +/- 12 nM (5 separate fetuses). Concentrations of GRP in excess of 160 nM caused a sharp reduction in both cell replication and DNA synthesis. To determine where within the cell cycle GRP exerted its mitogenic action, synchronized chondrocytes were transiently exposed to fetal bovine serum and cultured with GRP for increasing periods of time before pulse labeling with [3H]thymidine during S phase. GRP was as effective in stimulating DNA synthesis when present for the initial 4 h of G1 as when present for the entire G1 period. Since isolated fetal growth plate chondrocytes release insulin-like growth factor II (IGF II) and basic fibroblast growth factor (basic FGF) the possible mediation of GRP action by the release of these peptides or synergistic interactions were examined. Specific antibodies shown to negate the mitogenic actions of exogenous IGFs or basic FGF on chondrocytes did not alter GRP-stimulated DNA synthesis. The release of radioimmunoassayable IGF II by chondrocytes was not altered in the presence of GRP. Coincubation of GRP with submaximal concentrations of IGF I or basic FGF showed additive effects on DNA synthesis. When the actions of galanin were examined it was found to inhibit basal DNA synthesis by chondrocytes at a concentration of 167 nM. However, 66 nM or greater galanin was able to render 160 nM GRP inactive as a mitogen. These results suggest that GRP may potentially influence skeletal development in the ovine fetus and may interact with locally released peptide growth factors or other neuropeptides.
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PMID:Mitogenic action of gastrin-releasing polypeptide on isolated epiphyseal growth plate chondrocytes from the ovine fetus. 157 94

Extracts of human term amnion, placenta, and chorion/decidual tissue (n = 5) contained gastrin-releasing peptide-like immunoreactivity (GRPLI) in amounts of 4.7 +/- 2.9 (pmol/g wet wt; mean +/- SEM), 3.6 +/- 1.1 and 2.9 +/- 1.5, respectively. Using C-terminally directed antisera and gel filtration chromatography and reverse-phase high-performance liquid chromatography (HPLC), each tissue contained molecular forms consistent with the presence of GRP1-27 and GRP18-27 but also contained larger amounts of two GRPLI peaks, which apparently are novel GRP-like peptides. In contrast, tissue extracts of human fetal lung contained only GRP1-27, GRP14-27, and GRP18-27. Using RT-PCR and specific GRP primers and probes, messenger RNA encoding for GRP was readily demonstrable from 6-weeks gestation throughout pregnancy to term in full-thickness membranes, placental villi, and decidua. Positive immunohistochemical staining for GRP occurred in extravillous trophoblasts in decidual septa and fetal membranes, cytotrophoblasts, syncytiotrophoblast, and certain stromal cells in placental villi and amniotic epithelium. GRPLI and GRP messenger RNA were present from the earliest dates examined (6-9 weeks) throughout pregnancy to term. Given the proven trophic nature of GRP and related peptides, these peptides may play important roles in maternal, placental, and fetal development during human pregnancy.
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PMID:Gastrin-releasing peptide-like immunoreactivity is present in human maternal and fetal placental membranes. 885 36