# CALCIOTROPIC HORMONES IN THE UTEROPLACENTAL UNIT

> **NIH NIH R01** · UNIVERSITY OF VIRGINIA · 1994 · $161,262

## Abstract

This laboratory is focused on calciotropic hormones in reproduction and
development, with special emphasis on the uteroplacental units of mice
and humans.  This proposal is focused on parathyroid hormone-related
protein (PTRrP), a hormone that inhibits uterine contractions (in rats),
increases placental calcium transport (in sheep), and relaxes vascular
smooth muscles in a variety of systems.  The present studies continue
work which identified abundant expression of PTHrP in human amnion and
documented its decrease following rupture of the amniotic sac.  Central
hypotheses of the studies are (1) that PTHrP expression in human amnion
is increased by mechanical signal transduction ("stretch"), is decreased
by loss of stretch (e.g., as occurs after rupture of the amniotic sac),
and is regulated by key hormones and growth factors of the uteroplacental
unit, and (2) that uterus and placental blood vessels are target tissues
for PTHrP in the human uteroplacental unit.  The specific aims are: (1).
To identify the mechanisms that control PTHRP expression in human amnion.
This will be accomplished by in vitro studies of amnion cells (a)
subjected to stretch, (b) treated with hormones (e.g., 1,25(OH)2 vitamin
D) and growth factors (e.g., EGF) of the uteroplacental unit, and (c)
treated with probes (e.g. phorbol esters, forskolin, calcium ionophore)
of the likely signal-transduction pathways. (2) To identify candidate
target tissues for PTHrP in the human uteroplacental unit.  This will be
accomplished by studies of binding of PTHrP, PTH and hormone fragments
and characterization of PTH/PTHrP receptor mRNA in these tissues. (3) To
define the cellular and subcellular localization of PTHrP and PTHrP mRNA
within the (multi-layered) human amnion.  This will be accomplished by
light and electron microscopic immunochemical studies with antibodies
directed against key regions of the PTHrP molecule.  Because PTHrP
relaxes uterine and vascular smooth muscle, these studies have potential
importance for understanding mechanisms that produce premature uterine
contractions (and thus, premature birth) and intrauterine growth
retardation associated with impaired placental blood flow.

## Key facts

- **NIH application ID:** 2196901
- **Project number:** 5R01HD012335-14
- **Recipient organization:** UNIVERSITY OF VIRGINIA
- **SAM.gov UEI:** JJG6HU8PA4S5
- **Principal Investigator:** M E BRUNS
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1994
- **Award amount:** $161,262
- **Award type:** 5
- **Project period:** 1978-12-01 → 1996-06-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2196901

## Citation

> US National Institutes of Health, RePORTER application 2196901, CALCIOTROPIC HORMONES IN THE UTEROPLACENTAL UNIT (5R01HD012335-14). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2196901. Licensed CC0.

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