Characterization of central melatonin receptors using 125I-melatonin

FEBS Lett. 1986 Mar 3;197(1-2):9-12. doi: 10.1016/0014-5793(86)80287-3.

Abstract

The binding of 125I-melatonin, a potent analog of melatonin, to rat brain synaptosomal preparations was investigated. 125I-melatonin bound with high affinity (Kd = 38 nM) to a single class of sites (Bmax = 81 fmol/mg protein). Kinetic studies indicated that binding was time-dependent and reversible. Specific 125I-melatonin binding was inhibited by melatonin, and was unaffected by other structurally related compounds including serotonin. Binding of 125I-melatonin was greatly reduced if the synaptosomal preparations were pretreated by heat or trypsin but was unaffected by freeze-thawing. These results suggest that 125I-melatonin may serve as a valuable probe for studying melatonin receptors.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Brain / metabolism*
  • Freezing
  • Hot Temperature
  • Hydroxyindoleacetic Acid / pharmacology
  • Iodine Radioisotopes
  • Kinetics
  • Male
  • Melatonin / analogs & derivatives*
  • Melatonin / metabolism
  • Melatonin / pharmacology
  • Rats
  • Receptors, Cell Surface / drug effects
  • Receptors, Cell Surface / metabolism*
  • Receptors, Melatonin
  • Serotonin / pharmacology
  • Synaptosomes / metabolism*
  • Trypsin / pharmacology

Substances

  • Iodine Radioisotopes
  • Receptors, Cell Surface
  • Receptors, Melatonin
  • Serotonin
  • Hydroxyindoleacetic Acid
  • 2-iodomelatonin
  • Trypsin
  • Melatonin