Abstract |
In the last years, a parathyroid hormone ( PTH)-related peptide ( PTHrP) has been isolated from tumors associated with humoral hypercalcemia with malignancy (HHM). In the present work, we studied the effect of bovine PTH (bPTH)(1-34) and PTHrP(1-34) on tartrate-resistant acid phosphatase (TRAP), a marker of bone resorption, and alkaline phosphatase (AP) activities, and basal and vitamin D-stimulated osteocalcin (BGP) synthesis (markers of bone formation) in fetal rat calvaria cultures. After a 48-hour incubation period, both bPTH(1-34) and PTHrP(1-34) caused an increase in TRAP activity liberated in the medium with respect to control cultured calvaria. On the other hand, while after 2 or 4 h of incubation both bPTH(1-34) and PTHrP(1-34) caused a decrease in the AP activity liberated in the medium, after 48 h of incubation both peptides caused a significant increase in the AP liberated in the medium with respect to control cultures. With respect to BGP synthesis, both bPTH(1-34) and PTHrP(1-34) antagonized the 1,25-dihydroxyvitamin D3 stimulatory effect in calvaria cultures. We conclude that PTHrP(1-34) causes similar effects on bone, in organ cultures, to those caused by bPTH(1-34), namely an increase in both bone resorption and formation and a decrease in the vitamin D-stimulated BGP synthesis.
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Authors | R Torres, C de la Piedra, A Rapado |
Journal | Mineral and electrolyte metabolism
(Miner Electrolyte Metab)
Vol. 19
Issue 2
Pg. 64-70
( 1993)
ISSN: 0378-0392 [Print] Switzerland |
PMID | 8377726
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Chemical References |
- Parathyroid Hormone
- Parathyroid Hormone-Related Protein
- Peptide Fragments
- Proteins
- Tartrates
- Osteocalcin
- parathyroid hormone (1-34), bovine
- Alkaline Phosphatase
- Acid Phosphatase
- Calcitriol
- tartaric acid
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Topics |
- Acid Phosphatase
(metabolism)
- Alkaline Phosphatase
(metabolism)
- Animals
- Bone and Bones
(drug effects, embryology, metabolism)
- Calcitriol
(pharmacology)
- Cells, Cultured
- Osteocalcin
(biosynthesis)
- Parathyroid Hormone
(pharmacology)
- Parathyroid Hormone-Related Protein
- Peptide Fragments
(pharmacology)
- Proteins
(pharmacology)
- Rats
- Rats, Wistar
- Tartrates
(pharmacology)
- Time Factors
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