Open AccessNeurotensin: specific binding to synaptic membranes from rat brain.
Author(s) -
Patrick Kitabgi,
Robert E. Carraway,
J Van Rietschoten,
Claude Granier,
JeanLouis Morgat,
Andre Ménèz,
Susan E. Leeman,
P Freychet
Publication year - 1977
Publication title -
proceedings of the national academy of sciences of the united states of america
Language(s) - English
Resource type - Journals
eISSN - 1091-6490
pISSN - 0027-8424
DOI - 10.1073/pnas.74.5.1846
Subject(s) - neurotensin , pentapeptide repeat , membrane , potency , neuropeptide , binding site , biophysics , incubation , chemistry , arginine , biochemistry , residue (chemistry) , non competitive inhibition , biology , peptide , enzyme , in vitro , amino acid , receptor
The binding of neurotensin to synaptic membranes from rat brain was studied at 24 degrees with the use of [3H]neurotensin. The binding was found to be highly specific, saturable, and reversible. Values for KD of 2 nM and 0.9 nM were derived from equilibrium and kinetic experiments, respectively. Virtually no degradation of neurotensin was observed in the incubation medium after exposure to synaptic membranes under the conditions of the binding studies. Competitive inhibition of [3H]neurotensin binding by partial sequences of neurotensin revealed that the addition of the residue arginine-8 to the neurotensin-(9-13)-pentapeptide increases about 500-fold the relative binding potency, whereas the remaining portion of the NH2-terminal region is mainly responsible for full pharmacological potency; the COOH-terminal leucyl residue is essential for binding.