scholarly journals Parathyroid hormone-related protein(1-34) in gestational fluids and release from human gestational tissues

2000 ◽  
Vol 165 (3) ◽  
pp. 657-662 ◽  
Author(s):  
W Farrugia ◽  
PW Ho ◽  
GE Rice ◽  
JM Moseley ◽  
M Permezel ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Amniotic Fluid ◽  
G Protein ◽  
Calcium Transport ◽  
Fetal Membranes ◽  
Related Protein ◽  
Parathyroid Hormone Related Protein ◽  
Gestational Tissues ◽  
Epithelial Growth ◽  
Stimulation Of

Parathyroid hormone-related protein (PTHrP) is present in fetal and gestational tissues, in which its proposed roles include stimulation of epithelial growth and differentiation, vasodilatation of the uteroplacental vasculature, relaxation of uterine muscle and stimulation of placental calcium transport. The aim of this study was to determine whether the release of PTHrP from gestational tissue explants was tissue specific. In addition, PTHrP concentrations were measured in maternal plasma, umbilical artery and vein plasma, and amniotic fluid from term, uncomplicated pregnancies before the onset of labour. PTHrP was detected in low concentrations in the mother, fetus and placental tissue. Amniotic fluid had ten times the PTHrP concentration compared with that in the maternal or fetal circulations. Using late pregnant human gestational tissues in an in vitro explant system, we found that amnion over placenta, choriodecidua, reflected amnion, and placenta released PTHrP into culture medium in progressively greater amounts over 24 h (P<0.05). This release was not associated with a loss of cell membrane integrity, as indicated by measurement of the intracellular enzyme, lactate dehydrogenase, in the incubation media. After 24 h incubation, the fetal membranes released significantly (P<0.05) greater amounts of PTHrP than did the placenta (placenta 3. 7+/-0.5 pmol PTHrP/g protein). Amnion over placenta released significantly more PTHrP (139.3+/- 43.1 pmol PTHrP/g protein) than did reflected amnion (29.0+/-8.3 pmol PTHrP/g protein) (P<0.05). This study unequivocally demonstrated that human gestational tissues release PTHrP and it was concluded that the main contributors to PTHrP in amniotic fluid were the human fetal membranes, particularly amnion over placenta. Fetal membrane-derived and amniotic fluid PTHrP are proposed to have stimulatory effects on epithelial growth and differentiation in fetal lung, gut, skin and hair follicles and paracrine effects on placental vascular tone and calcium transport.

The expression of parathyroid hormone-related protein mRNA and immunoreactive protein in human amnion and choriodecidua is increased at term compared with preterm gestation

1997 ◽  
Vol 154 (1) ◽  
pp. 103-112 ◽  
Author(s):  
N E Curtis ◽  
P W M Ho ◽  
R G King ◽  
W Farrugia ◽  
E K Moses ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Caesarean Section ◽  
Normal Vaginal Delivery ◽  
Smooth Muscle Relaxation ◽  
Fetal Membranes ◽  
Related Protein ◽  
Immunoreactive Protein ◽  
Parathyroid Hormone Related Protein ◽  
Gestational Tissues ◽  
Term Labour

Abstract Parathyroid hormone-related protein (PTHrP) gene expression and/or immunoreactive protein have previously been identified in the uterus and intrauterine gestational tissues. The putative roles of PTHrP during pregnancy include vasodilatation, regulation of placental calcium transfer, uterine smooth muscle relaxation and normal fetal development. The aims of this study were 1) to determine the tissue-specific and temporal expression of PTHrP mRNA and immunoreactive protein in human gestational tissues collected at preterm and term; and 2) to determine the effect of labour on PTHrP expression by collecting these tissues from women undergoing elective caesarean section (before labour), intra-partum caesarean section during spontaneous-onset labour (during labour), and women with spontaneous labour and normal vaginal delivery (after labour). Total RNA and protein were extracted from placenta, amnion (over placenta and reflected) and choriodecidua for analysis by Northern blot (using a specific human PTHrP cDNA probe), and by N-terminal PTHrP RIA respectively. In amnion over placenta, reflected amnion and choriodecidua both PTHrP mRNA relative abundance and immunoreactive protein were significantly elevated at term compared with preterm (P<0·01). At term, both PTHrP and its mRNA were significantly greater in amnion than in placenta and choriodecidua (P<0·05). Also, both PTHrP and its mRNA were significantly elevated in amnion over placenta compared with reflected amnion (P<0·05). The expression of PTHrP and its mRNA did not change in association with term labour or rupture of the fetal membranes, therefore this study provides no evidence for a specific PTHrP role in the onset and/or maintenance of term labour. However, the significant up-regulation of PTHrP mRNA and protein in the fetal membranes at term compared with preterm suggests an important role in late human pregnancy. Journal of Endocrinology (1997) 154, 103–112

scholarly journals Parathyroid hormone-related protein regulates intestinal calcium transport in sea bream (Sparus auratus)

2006 ◽  
Vol 291 (5) ◽  
pp. R1499-R1506 ◽  
Author(s):  
Juan Fuentes ◽  
Joana Figueiredo ◽  
Deborah M. Power ◽  
Adelino V. M. Canário
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Transport ◽  
Calcium Uptake ◽  
Sea Bream ◽  
Whole Body ◽  
Related Protein ◽  
Parathyroid Hormone Related Protein ◽  
Intestinal Calcium Transport ◽  
Sparus Auratus

Parathyroid hormone-related protein (PTHrP) is a factor associated with normal development and physiology of the nervous, cardiovascular, immune, reproductive, and musculoskeletal systems in higher vertebrates. It also stimulates whole body calcium uptake in sea bream ( Sparus auratus) larvae with an estimated 60% coming from intestinal uptake in seawater. The present study investigated the role of PTHrP in the intestinal calcium transport in the sea bream in vitro. Unidirectional mucosal-to-serosal and serosal-to-mucosal 45Ca fluxes were measured in vitro in duodenum, hindgut, and rectum mounted in Ussing chambers. In symmetric conditions with the same saline, bathing apical and basolateral sides of the preparation addition of piscine PTHrP 1–34 (6 nM) to the serosal surface resulted in an increase in mucosal to serosal calcium fluxes in duodenum and hindgut and a reduction in serosal to mucosal in the rectum, indicating that different mechanisms are responsive to PTHrP along the intestine. In control asymmetric conditions, with serosal normal and mucosal bathed with a saline similar in composition to the intestinal fluid, there was a net increase in calcium uptake in all regions. The addition of 6 nM PTHrP 1–34 increased net calcium uptake two- to threefold in all regions. The stimulatory effect of PTHrP on net intestinal calcium absorption is consistent with a hypercalcemic role for the hormone. The results support the view that PTHrP, alone or in conjunction with recently identified PTH-like peptides, counteracts in vivo the hypocalcemic effects of stanniocalcin.

Placental adaptive up-regulation of calcium transport in wild-type mice is not driven by parathyroid hormone-related protein (PTHrP)

Placenta ◽  
2016 ◽  
Vol 45 ◽  
pp. 128
Author(s):  
Christina Hayward ◽  
Kirsty McIntyre ◽  
Colin Sibley ◽  
Susan Greenwood ◽  
Mark Dilworth
Keyword(s):  
Parathyroid Hormone ◽  
Calcium Transport ◽  
Related Protein ◽  
Wild Type ◽  
Parathyroid Hormone Related Protein

Cortisol, parathyroid hormone-related protein and the onset of calcium secretion by the mammary gland of the goat

1997 ◽  
Vol 64 (4) ◽  
pp. 633-636
Author(s):  
GORDON E. THOMPSON ◽  
S. KHAWAR ABBAS ◽  
CARL HOLT ◽  
ANTHONY D. CARE
Keyword(s):  
Mammary Gland ◽  
Parathyroid Hormone ◽  
Epithelial Cells ◽  
Tight Junctions ◽  
Calcium Transport ◽  
Extracellular Fluid ◽  
Secretory Cells ◽  
Related Protein ◽  
Parathyroid Hormone Related Protein ◽  
Calcium Secretion

During lactogenesis in the goat, the onset of secretion of calcium into milk occurs at parturition (Thompson et al. 1995) at approximately the same time as the onset of secretion of parathyroid hormone-related protein (PTHrP) by the mammary gland (Ratcliffe et al. 1992); these events may be unrelated or PTHrP may be involved in calcium transport from blood to milk.Parturition in goats is initiated by fetal secretion of cortisol (Flint et al. 1978) and maternal secretion of cortisol also increases (Paterson & Linzell, 1971). Injecting cortisol locally into the sinus of a mammary gland of the late-pregnant goat when the tight junctions between secretory epithelial cells appear to be ‘loose’, and injectate can reach the basolateral surfaces of secretory cells, stimulates an early tightening of these junctions (Thompson, 1996) as occurs naturally at parturition. This tightening can be produced by an increased concentration of ionized calcium in the extracellular fluid of the gland (Neville & Peaker, 1981).The experiments reported here were undertaken to determine if cortisol injection stimulates the mammary gland to secrete both PTHrP and calcium before parturition.

Parathyroid hormone-related protein in human term placenta and membranes

1994 ◽  
Vol 142 (2) ◽  
pp. 217-224 ◽  
Author(s):  
S J Bowden ◽  
J F Emly ◽  
S V Hughes ◽  
G Powell ◽  
A Ahmed ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Caesarean Section ◽  
Amniotic Fluid ◽  
Elective Caesarean Section ◽  
Molecular Forms ◽  
Molecular Heterogeneity ◽  
Related Protein ◽  
Human Term Placenta ◽  
Parathyroid Hormone Related Protein ◽  
Spontaneous Labour

Abstract Parathyroid hormone-related protein (PTHrP), the hypercalcaemia of malignacy factor, is expressed in the tissues of the human uteroplacental unit, including the placenta, amnion and chorion. We have used three region-specific immunoassays to quantitate and compare the distribution of PTHrP in tissues obtained at term following spontaneous labour and vaginal delivery or elective Caesarean section. In non-labouring women highest PTHrP(1–86) and (37–67) immunoreactivity was found in amnion covering the placenta, rather than the decidua parietalis of the uterus (reflected amnion) (median 1020 vs 451 fmol/g; 2181 vs 1444 fmol/g respectively). In labouring women, the PTHrP(1–86) concentration in reflected amnion was inversely correlated with the interval between rupture of the membranes and delivery. Tissue PTHrP(1–86) concentrations were lower in placenta than in chorion and amnion (medians 12, 109 and 664 fmol/g respectively) and, in all tissues, PTHrP(1–34) and (37–67) concentrations were significantly higher than that of PTHrP(1–86). Bioactive PTHrP(1–34) was detected in placenta, chorion and amnion using the ROS cell bioassay. The PTHrP(1–86) concentration (mean ± s.e.m.=41·4 ± 4·5 pmol/l) was high in amniotic fluid at term, although in maternal and cord plasma levels were only modestly increased. The molecular forms of PTHrP present in tissues and amniotic fluid were investigated by column chromatography which confirmed its molecular heterogeneity and suggested that processing is tissue-specific and occurs at both amino- and carboxy-terminals of the peptide. Journal of Endocrinology (1994) 142, 217–224

Parathyroid hormone-related protein (PTHrP) concentrations in human amniotic fluid during gestation and at the time of labour

1995 ◽  
Vol 7 (6) ◽  
pp. 1509 ◽  
Author(s):  
ME Wlodek ◽  
PW Ho ◽  
GE Rice ◽  
JM Moseley ◽  
TJ Martin ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Amniotic Fluid ◽  
Gestational Age ◽  
Late Gestation ◽  
Physiological Significance ◽  
Fetal Membrane ◽  
Related Protein ◽  
Human Amniotic Fluid ◽  
Membrane Function ◽  
Parathyroid Hormone Related Protein

To establish the changes associated with gestational age and labour status in parathyroid hormone-related protein (PTHrP) concentrations in the amniotic fluid, human amniotic fluid was collected from non-labouring and labouring women at < 37 weeks of gestation (preterm) and at term (> or = 37 weeks). PTHrP was assayed by a specific N-terminal radioimmunoassay. PTHrP concentrations in amniotic fluid obtained from non-labouring women were significantly lower at preterm (15-36 weeks; 14.1 +/- 2.5 pmol L(-1); n = 11) than at term (37-42 weeks; 39.3 +/- 7.6 pmol L(-1); n = 16; P < 0.0009). Concentrations of PTHrP in amniotic fluid obtained from labouring women were also significantly lower at preterm (27-36 week; 12.2 +/- 4.7 pmol L(-1); n = 4; P < 0.01) than at term (37-42 weeks; 63. 8 +/- 19.6 pmol L(-1); n = 9). There were no significant changes in concentration associated with labour status, either at preterm or at term. The physiological significance of elevated amniotic fluid concentrations of PTHrP has yet to be established, but the data are consistent with the suggestion that PTHrP plays a role in fetal membrane function during late gestation.

Transforming growth factor β stimulation of parathyroid hormone-related protein (PTHrP): a paracrine regulator?

1993 ◽  
Vol 94 (1) ◽  
pp. 145 ◽  
Author(s):  
Takeshi Kiriyama ◽  
Matthew T. Gillespie ◽  
Jane A. Glatz ◽  
Seiji Fukumoto ◽  
jane M. Moseley ◽  
...  
Keyword(s):  
Parathyroid Hormone ◽  
Growth Factor ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β ◽  
Related Protein ◽  
Parathyroid Hormone Related Protein ◽  
Stimulation Of
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