# THE CALCIOTROPIC HORMONES

> **NIH NIH R01** · UNIVERSITY OF CALIFORNIA, SAN DIEGO · 1988 · $187,791

## Abstract

We propose to study the interactions among the calcitropic hormones,
parathyroid hormone (PTH), calcitonin (CT) and 1,25
dihydroxycholecalciferol (1,25DHCC); their interactions with other hormones
important in skeletal metabolism, such as gonadal and adrenal steroids; and
their effects on their target organs.  Studies will also be made of
proteins and peptides related to the calcemic hormones, such as
calcitonin-gene-related peptide (CGRP) and Endocrine Secretory Protein
(ESP, a.k.a. PSP, SP-I, Chr A).  The studies will be conducted in vitro and
in vivo in humans and experimental animals.  In vitro studies will be
conducted in cell, tissue, and organ cultures which produce calcitonin,
PTH, CGRP, and ESP.  The effects of the calcitropic hormones on the
skeletal system will be assessed by newly developed immunochemical
procedures for measuring bone gla protein, bone alkaline phosphatase,
matrix gla protein and osteonectin.  Regulation in these systems will be
evaluated by classical techniques as well as the new approaches of
molecular biology.  Hormone biosynthesis and secretion will be studied with
in vitro models which can then be ued as the bases for the design of
corresponding in vivo studies.  In vivo studies in humans will be
complemented by detailed studies in rats, selected studies in artiodactyls,
and marine biology studies in fish representative of differing habitudes
and skeletal systems.  The studies will utilize extant and newly developed
radioassays and related biochemical, immunochemical, and
immunohistochemical procedures; many of these methods will be based on
monoclonal antibodies.  The hormone assay procedures will be designed to
directly and indirectly assess biological activity.  Monoclonal antibody
technology and recombinant DNA procedures will also be used.  Regulatory
studies will be conducted of physiological variables such as gender and
aging and of selected aspects of human disease states and relevant animal
models.  These disease states include hypercalciuria, hypercalcemia,
William's syndrome, Paget's disease, renal osteodystrophy and
osteoporosis.  These studies of the interactions among the calcitropic
hormones, their biosynthesis and secretion, their target organ effects, and
their molecular biology should provide basic information and clinically
useful data about their role in physiology and pathophysiology.

## Key facts

- **NIH application ID:** 3154855
- **Project number:** 5R01AR015888-16
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN DIEGO
- **SAM.gov UEI:** UYTTZT6G9DT1
- **Principal Investigator:** LEONARD JOHN DEFTOS
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 1988
- **Award amount:** $187,791
- **Award type:** 5
- **Project period:** 1976-05-01 → 1989-04-30

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/3154855

## Citation

> US National Institutes of Health, RePORTER application 3154855, THE CALCIOTROPIC HORMONES (5R01AR015888-16). Retrieved via MORVS 2026-10-24 from https://api.morvs.ai/grant/nih/3154855. Licensed CC0.

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