'Perinatal Research Centre, Department of Perinatal Medicine, Royal Women's Hospital, ... -â¢Department of Medicine and St Vincent's Institute of Medical Research, Fitzroy, ...... Chen EY, Hudson PJ, Martin TJ & Wood WI 1987 A parathyroid.
of parathyroid hormone-related protein mRNA and immunoreactive protein in human amnion and choriodecidua is increased at term compared with
The
expression
preterm gestation
N E Curtis, P W M M T Gillespie, J M
Ho, R G King, W Farrugia, E K Moses, Moseley, G E Rice and M E Wlodek
'Perinatal Research Centre, Department of Perinatal Medicine, Royal Women's Hospital, Carlton, Victoria 3053, Australia, 2Department of Physiology, University of Melbourne, Parkville, Victoria 3052, Australia, 'Department of Pharmacology, Monash University, Clayton, Victoria 3168, Australia, -•Department of Medicine and St Vincent's Institute of Medical Research, Fitzroy, Victoria 3065, Australia and 5Department of Obstetrics and Gynaecology, University of Melbourne, Parkville, Victoria 3052, Australia (Requests for offprints should be addressed to E Curtis, Perinatal Research Centre, Department of Perinatal Medicine, Royal Women's Hospital, Carlton, Victoria 3053, Australia)
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 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 the
Introduction
Parathyroid hormone-related protein (PTHrP) was originally isolated and cloned from tumours associated with humoral hypercalcaemia of malignancy (Moseley et al.
1987, Stewart et al. 1987, Strewler et al. 1987, Suva et al. 1987, Mangin et al. 1988). It has since become apparent
that PTHrP is produced by, and has physiological roles in, many non-malignant tissues including fetal, reproductive and gestational tissues (Thiede 1992, Rodda & Moseley 1993). PTHrP mRNA expression and immunoreactive PTHrP have been identified in uterus, placenta and in the fetal membranes, amnion and chorion (De Papp & Stewart
N-terminal PTHrP RIA respectively. In amnion over placenta, reflected amnion and choriodecidua both PTHrP
mRNA relative abundance and immunoreactive protein significantly elevated at term compared with preterm (P
