Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes
Abstract
Guanine nucleotides and pertussis toxin were used to investigate whether somatostatin receptors interact with the guanine nucleotide inhibitory protein (NI) on pancreatic acinar membranes in the rat. Guanine nucleotides reduced /sup 125/I-(Tyr/sup 1/)somatostatin binding to acinar membranes up to 80%, with rank order of potency being 5'-guanylyl imidodiphosphate (Gpp(NH)p)>GTP>TDP>GMP. Scatchard analysis revealed that the decrease in somatostatin binding caused by Gpp(NH)p was due to the decrease in the maximum binding capacity without a significant change in the binding affinity. The inhibitory effect of Gpp(NH)p was partially abolished in the absence of Mg/sup 2 +/. When pancreatic acini were treated with 1 ..mu..g/ml pertussis toxin for 4 h, subsequent /sup 125/I-(Tyr/sup 1/)somatostatin binding to acinar membranes was reduced. Pertussis toxin treatment also abolished the inhibitory effect of somatostatin on vasoactive intestinal peptide-stimulated increase in cellular content of adenosine 3',5'-cyclic monophosphate (cAMP) in the acini. The present results suggest that 1) somatostatin probably functions in the pancreas to regulate adenylate cyclase enzyme system via Ni, 2) the extent of modification of Ni is correlated with the ability of somatostatin to inhibit cAMP accumulation in acini, and 3) guanine nucleotides also inhibit somatostatin binding to its receptor.
- Authors:
- Publication Date:
- Research Org.:
- Kobe Univ. School of Medicine (Japan)
- OSTI Identifier:
- 6863525
- Resource Type:
- Journal Article
- Journal Name:
- Am. J. Physiol.; (United States)
- Additional Journal Information:
- Journal Volume: 253:3
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 62 RADIOLOGY AND NUCLEAR MEDICINE; 59 BASIC BIOLOGICAL SCIENCES; CELL MEMBRANES; AUTORADIOGRAPHY; PROTEINS; BIOCHEMISTRY; SOMATOSTATIN; RADIORECEPTOR ASSAY; AMP; CYCLASES; ELECTROPHORESIS; GUANINE; IODINE 125; NUCLEOTIDES; PHOSPHORUS 32; RECEPTORS; SODIUM IODIDES; TOXINS; TYROSINE; ALKALI METAL COMPOUNDS; AMINES; AMINO ACIDS; ANTIGENS; AROMATICS; AZAARENES; BETA DECAY RADIOISOTOPES; BETA-MINUS DECAY RADIOISOTOPES; CARBOXYLIC ACIDS; CELL CONSTITUENTS; CHEMISTRY; DAYS LIVING RADIOISOTOPES; ELECTRON CAPTURE RADIOISOTOPES; ENZYMES; HALIDES; HALOGEN COMPOUNDS; HETEROCYCLIC COMPOUNDS; HYDROXY ACIDS; HYDROXY COMPOUNDS; INORGANIC PHOSPHORS; INTERMEDIATE MASS NUCLEI; IODIDES; IODINE COMPOUNDS; IODINE ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; LIGHT NUCLEI; LYASES; MATERIALS; MEMBRANE PROTEINS; MEMBRANES; NUCLEI; ODD-EVEN NUCLEI; ODD-ODD NUCLEI; ORGANIC ACIDS; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; PHOSPHORS; PHOSPHORUS ISOTOPES; PURINES; RADIOISOTOPES; SODIUM COMPOUNDS; TOXIC MATERIALS; TRACER TECHNIQUES; 550601* - Medicine- Unsealed Radionuclides in Diagnostics; 550201 - Biochemistry- Tracer Techniques
Citation Formats
Sakamoto, C, Matozaki, T, Nagao, M, and Baba, S. Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes. United States: N. p., 1987.
Web. doi:10.1507/endocrine1927.63.8_978.
Sakamoto, C, Matozaki, T, Nagao, M, & Baba, S. Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes. United States. https://doi.org/10.1507/endocrine1927.63.8_978
Sakamoto, C, Matozaki, T, Nagao, M, and Baba, S. 1987.
"Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes". United States. https://doi.org/10.1507/endocrine1927.63.8_978.
@article{osti_6863525,
title = {Coupling of guanine nucleotide inhibitory protein to somatostatin receptors on pancreatic acinar membranes},
author = {Sakamoto, C and Matozaki, T and Nagao, M and Baba, S},
abstractNote = {Guanine nucleotides and pertussis toxin were used to investigate whether somatostatin receptors interact with the guanine nucleotide inhibitory protein (NI) on pancreatic acinar membranes in the rat. Guanine nucleotides reduced /sup 125/I-(Tyr/sup 1/)somatostatin binding to acinar membranes up to 80%, with rank order of potency being 5'-guanylyl imidodiphosphate (Gpp(NH)p)>GTP>TDP>GMP. Scatchard analysis revealed that the decrease in somatostatin binding caused by Gpp(NH)p was due to the decrease in the maximum binding capacity without a significant change in the binding affinity. The inhibitory effect of Gpp(NH)p was partially abolished in the absence of Mg/sup 2 +/. When pancreatic acini were treated with 1 ..mu..g/ml pertussis toxin for 4 h, subsequent /sup 125/I-(Tyr/sup 1/)somatostatin binding to acinar membranes was reduced. Pertussis toxin treatment also abolished the inhibitory effect of somatostatin on vasoactive intestinal peptide-stimulated increase in cellular content of adenosine 3',5'-cyclic monophosphate (cAMP) in the acini. The present results suggest that 1) somatostatin probably functions in the pancreas to regulate adenylate cyclase enzyme system via Ni, 2) the extent of modification of Ni is correlated with the ability of somatostatin to inhibit cAMP accumulation in acini, and 3) guanine nucleotides also inhibit somatostatin binding to its receptor.},
doi = {10.1507/endocrine1927.63.8_978},
url = {https://www.osti.gov/biblio/6863525},
journal = {Am. J. Physiol.; (United States)},
number = ,
volume = 253:3,
place = {United States},
year = {Tue Sep 01 00:00:00 EDT 1987},
month = {Tue Sep 01 00:00:00 EDT 1987}
}