Open AccessVasoactive intestinal polypeptide: specific binding to rat brain membranes.
Author(s) -
Duncan P. Taylor,
Candace B. Pert
Publication year - 1979
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 5.011
H-Index - 771
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.76.2.660
Subject(s) - vasoactive intestinal peptide , secretin , cerebral cortex , membrane , striatum , neuropeptide , biology , hippocampus , binding site , hypothalamus , receptor , endocrinology , cortex (anatomy) , biochemistry , chemistry , medicine , secretion , neuroscience , dopamine
The binding of radiolabeled vasoactive intestinal polypeptide (VIP) to rat brain membranes was investigated. Specific binding of 125I-labeled VIP was reversible and saturable (Bmax = 2.2 pmol/g of wet tissue). Brain membranes exhibited a high affinity for 125I-labeled VIP (KD = 1 nM) at a single class of noninteracting sites. Binding of 125I-labeled VIP paralleled its immunohistochemical localization, being enriched in cerebral cortex, hippocampus, striatum, and thalamus, with the notable exception of the hypothalamus, which had low levels of binding. The density of sites was greater in synaptosomal fractions relative to mitochondrial or nuclear fractions. Secretin and partial sequences of it and VIP inhibited binding to brain membranes with an order of potency similar to that found in other systems. The findings suggest the existence of a unique new class of brain receptors.