skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus

Abstract

1. The effect of melatonin on forskolin-stimulated adenylate cyclase activity was measured in homogenates of Syrian hamster hypothalamus. In addition, the saturation binding characteristics of the melatonin receptor ligand, ({sup 125}I)iodomelatonin, was examined using an incubation temperature (30{degree}C) similar to that used in enzyme assays. 2. At concentrations ranging from 10 pM to 1 nM, melatonin caused a significant decrease in stimulated adenylate cyclase activity with a maximum inhibition of approximately 22%. 3. Binding experiments utilizing ({sup 125}I)iodomelatonin in a range of approximately 5-80 pM indicated a single class of high-affinity sites: Kd = 55 +/- 9 pM, Bmax = 1.1 +/- 0.3 fmol/mg protein. 4. The ability of picomolar concentrations of melatonin to inhibit forskolin-stimulated adenylate cyclase activity suggests that this affect is mediated by picomolar-affinity receptor binding sites for this hormone in the hypothalamus.

Authors:
;  [1]
  1. (McMaster Univ.,Hamilton, ON (Canada))
Publication Date:
OSTI Identifier:
5639742
Resource Type:
Journal Article
Journal Name:
Cellular and Molecular Neurobiology; (USA)
Additional Journal Information:
Journal Volume: 10:4; Journal ID: ISSN 0272-4340
Country of Publication:
United States
Language:
English
Subject:
59 BASIC BIOLOGICAL SCIENCES; CYCLASES; ENZYME ACTIVITY; MELATONIN; BIOCHEMICAL REACTION KINETICS; AFFINITY; HAMSTERS; HYPOTHALAMUS; INHIBITION; IODINE 125; LIGANDS; RADIOASSAY; RECEPTORS; TRACER TECHNIQUES; AMINES; ANIMALS; AROMATICS; AZAARENES; AZOLES; BETA DECAY RADIOISOTOPES; BODY; BRAIN; CENTRAL NERVOUS SYSTEM; DAYS LIVING RADIOISOTOPES; ELECTRON CAPTURE RADIOISOTOPES; ENZYMES; HETEROCYCLIC COMPOUNDS; INDOLES; INTERMEDIATE MASS NUCLEI; INTERNAL CONVERSION RADIOISOTOPES; IODINE ISOTOPES; ISOTOPE APPLICATIONS; ISOTOPES; KINETICS; LYASES; MAMMALS; MEMBRANE PROTEINS; NERVOUS SYSTEM; NUCLEI; ODD-EVEN NUCLEI; ORGANIC COMPOUNDS; ORGANIC NITROGEN COMPOUNDS; ORGANS; PROTEINS; PYRROLES; RADIOISOTOPES; REACTION KINETICS; RODENTS; TRYPTAMINES; VERTEBRATES; 550201* - Biochemistry- Tracer Techniques

Citation Formats

Niles, L.P., and Hashemi, F. Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus. United States: N. p., 1990. Web. doi:10.1007/BF00712848.
Niles, L.P., & Hashemi, F. Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus. United States. doi:10.1007/BF00712848.
Niles, L.P., and Hashemi, F. Sat . "Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus". United States. doi:10.1007/BF00712848.
@article{osti_5639742,
title = {Picomolar-affinity binding and inhibition of adenylate cyclase activity by melatonin in Syrian hamster hypothalamus},
author = {Niles, L.P. and Hashemi, F.},
abstractNote = {1. The effect of melatonin on forskolin-stimulated adenylate cyclase activity was measured in homogenates of Syrian hamster hypothalamus. In addition, the saturation binding characteristics of the melatonin receptor ligand, ({sup 125}I)iodomelatonin, was examined using an incubation temperature (30{degree}C) similar to that used in enzyme assays. 2. At concentrations ranging from 10 pM to 1 nM, melatonin caused a significant decrease in stimulated adenylate cyclase activity with a maximum inhibition of approximately 22%. 3. Binding experiments utilizing ({sup 125}I)iodomelatonin in a range of approximately 5-80 pM indicated a single class of high-affinity sites: Kd = 55 +/- 9 pM, Bmax = 1.1 +/- 0.3 fmol/mg protein. 4. The ability of picomolar concentrations of melatonin to inhibit forskolin-stimulated adenylate cyclase activity suggests that this affect is mediated by picomolar-affinity receptor binding sites for this hormone in the hypothalamus.},
doi = {10.1007/BF00712848},
journal = {Cellular and Molecular Neurobiology; (USA)},
issn = {0272-4340},
number = ,
volume = 10:4,
place = {United States},
year = {1990},
month = {12}
}