# PLACENTAL RELAXIN--STRUCTURE AND SECRETION

> **NIH NIH R29** · EAST CAROLINA UNIVERSITY · 1993 · $72,701

## Abstract

Relaxin has been identified in term placentae of humans, and recently this
hormone was identified in trophoblast cells of the implanting blastocyst
and developing placenta of the hamster. The objectives of the proposed
research are to characterize hamster placental relaxin and examine the
secretion of relaxin using the hamster aa a model. Several experimental
protocols will be used. In the first study, relaxin will be isolated from
placentae and purified by chromatographic procedures. Molecular weight,
isoelectric point and amino acid sequence of the purified product will be
determine to allow comparison with relaxins from other species and tissues.
In the second study antiserum to purified hamster relaxin will produced and
an homologous hamster relaxin radioimmunoassay developed. This assay is
critical for studying placental relaxin in this species. In the third study
serum relaxin concentrations during gestation will be determined. In
addition, the kinetics of placental relaxin synthesis and secretion
(storage, rate, percentage of total protein synthesis, molecular weight of
secreted hormone) will be determined for several stages of gestation. These
variables will be examined by incubating placental explants with
radioactive amino acid and measuring incorporation into total protein and
relaxin. In study five the role of the pituitary and ovary in regulating
placental relaxin synthesis and secretion will be examined by measuring
serum and tissue hormone concentrations after removal of these organs after
different stages of gestation. These studies will provide information on
the biology of placental relaxin which may be useful in understanding its
role in establishment and maintenance of pregnancy.

## Key facts

- **NIH application ID:** 2198873
- **Project number:** 5R29HD023481-05
- **Recipient organization:** EAST CAROLINA UNIVERSITY
- **SAM.gov UEI:** HWPEKM8VFTJ9
- **Principal Investigator:** RANDALL HARRELL RENEGAR
- **Activity code:** R29 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1993
- **Award amount:** $72,701
- **Award type:** 5
- **Project period:** 1989-08-01 → 1995-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/2198873

## Citation

> US National Institutes of Health, RePORTER application 2198873, PLACENTAL RELAXIN--STRUCTURE AND SECRETION (5R29HD023481-05). Retrieved via MORVS 2026-10-25 from https://api.morvs.ai/grant/nih/2198873. Licensed CC0.

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