Guanine nucleotides are potent secretagogues in permeabilized parathyroid cells
| Autor: | Linda Swiston, Meryl S. LeBoff, Edward M. Brown, Joseph Preston, Marguerite Oetting |
|---|---|
| Rok vydání: | 1986 |
| Předmět: |
medicine.medical_specialty
GTP' Guanine Biophysics In Vitro Techniques Biochemistry Parathyroid Glands 03 medical and health sciences chemistry.chemical_compound 0302 clinical medicine Structural Biology Internal medicine Genetics medicine Animals Nucleotide Secretion Molecular Biology 030304 developmental biology Regulation of gene expression chemistry.chemical_classification 0303 health sciences Chemistry Nucleotides Binding protein PTH release Permeabilized cell Guanine nucleotide Ca2+ PTH secretion Cell Biology Parathyroid chief cell Guanine Nucleotides Endocrinology Parathyroid Hormone Calcium Cattle hormones hormone substitutes and hormone antagonists 030217 neurology & neurosurgery |
| Zdroj: | FEBS letters. 208(1) |
| ISSN: | 0014-5793 |
| Popis: | We studied the effects of GTP and its' analogues on PTH release in permeabilized parathyroid cells to assess their role in mediating the unusual inverse relationship between Ca2+ and PTH release in intact parathyroid cells. Both 10-5 M GppNHp and GTP gamma S, nonhydrolysable analogues of GTP, produce up to an 8-fold enhancement of PTH release, which is dose-dependent. This effect is specific for GTP analogues as we could not mimic it with other nucleotides. 10(-3) M GDP beta S, a nonhydrolysable GDP analogue, completely abolishes GppNHp-stimulated hormone release, providing further support for mediation of this effect by a guanine-nucleotide regulatory protein. In GppNHp-stimulated cells, PTH release is maximal at free [Ca2+] less than 200 nM and progressively decreases as the free [Ca2+] increases from 300 nM to 100 microM. These results suggest the presence of a guanine-nucleotide binding protein in the parathyroid cell that may play an important role in the regulation of PTH secretion by Ca2+ and perhaps other secretagogues. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text