Tumoral synthetic parathyroid hormone related peptide inhibits amiloride-sensitive sodium transport in cultured renal epithelia.

Abstract

The amino-terminal fragment of a tumor parathyroid hormone-related peptide (PTHrP(1-34] produced by a human squamous cell carcinoma of the lung was recently synthesized. In the present work its effect on the amiloride-sensitive sodium transport, taken as an estimate of the Na+/H+ exchanger activity of cultured opossum kidney (OK) epithelia was compared to that of synthetic bovine parathyroid hormone (bPTH(1-34]. Both PTHrP(1-34) and bPTH(1-34) inhibited the initial rate of amiloride-sensitive 22Na transport. Half maximal inhibitory activity was obtained at about 10(-11)M for both PTHrP(1-34) and bPTH(1-34). In conclusion, tumoral PTHrP(1-34) appears to be as effective as bPTH(1-34) for inhibiting the amiloride-sensitive Na transport, and presumably for decreasing the activity of the Na+/H+ exchanger present in the apical membrane of kidney epithelial cells.

• Authors: J Caverzasio, R Rizzoli, T J Martin, J P Bonjour
• Journal: Pflugers Archiv : European journal of physiology (Pflugers Arch) Vol. 413 Issue 1 Pg. 96-8 (Nov 1988) ISSN: 0031-6768 [Print] Germany
• PMID: 3217231 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Neoplasm Proteins
• Parathyroid Hormone
• Parathyroid Hormone-Related Protein
• Amiloride
• Sodium

Topics

• Amiloride (pharmacology)
• Animals
• Cells, Cultured
• Epithelial Cells
• Kidney (cytology, metabolism)
• Neoplasm Proteins (pharmacology)
• Opossums
• Parathyroid Hormone (pharmacology)
• Parathyroid Hormone-Related Protein
• Sodium (pharmacokinetics)