TY - JOUR
T1 - [125]I-Spectramide
T2 - A novel benzamide displaying potent and selective effects at the D2 dopamine receptor
AU - Sánchez-Roa, Patricia M.
AU - Grigoriadis, Dimitri E.
AU - Wilson, Alan A.
AU - Sharkey, John
AU - Dannals, Robert F.
AU - Villemagne, Victor L.
AU - Wong, Dean F.
AU - Wagner, Henry N.
AU - Kuhar, Michael J.
N1 - Funding Information:
Special thanks to Michele Milberger for her technical assistance and Terry Pierce for secretarial assistance. D.E.G. is a Medical Research Council of Canada post-doctoral fellow. This work was supported in part by USPHS grants NS-15080 and CA-32845 and by the NIDA Addiction Research Center.
PY - 1989
Y1 - 1989
N2 - The new substituted benzamide Spectramide, (N-[2-[4-iodobenzyl-N-methylamino]-2-methoxy-4-ethyl]-5-chloro-methylamine] benzamide) labelled with 125I was used as a potent and highly selective dopamine-D2 receptor antagonist in rat striatal homogenates for in vitro receptor binding. Kinetic experiments demonstrated the reversibility of the binding and the estimated Kd from saturation analysis was 25 pM, with a Bmax of 20 pmol/g of tissue. Competition studies showed that spectramide did not interact potently with the D1 or dopamine-uptake site. Drugs known to interact with other receptor systems were weak competitors of the binding, while binding was potently inhibited by other D2 antagonists, such as spiperone and eticlopride. These data indicate that Spectramide binds selectively and with high affinity to the dopamine D2 receptors, and may prove to be a useful tool for the study of these receptors in vivo using PET or SPECT.
AB - The new substituted benzamide Spectramide, (N-[2-[4-iodobenzyl-N-methylamino]-2-methoxy-4-ethyl]-5-chloro-methylamine] benzamide) labelled with 125I was used as a potent and highly selective dopamine-D2 receptor antagonist in rat striatal homogenates for in vitro receptor binding. Kinetic experiments demonstrated the reversibility of the binding and the estimated Kd from saturation analysis was 25 pM, with a Bmax of 20 pmol/g of tissue. Competition studies showed that spectramide did not interact potently with the D1 or dopamine-uptake site. Drugs known to interact with other receptor systems were weak competitors of the binding, while binding was potently inhibited by other D2 antagonists, such as spiperone and eticlopride. These data indicate that Spectramide binds selectively and with high affinity to the dopamine D2 receptors, and may prove to be a useful tool for the study of these receptors in vivo using PET or SPECT.
UR - https://www.scopus.com/pages/publications/0024471492
U2 - 10.1016/0024-3205(89)90523-7
DO - 10.1016/0024-3205(89)90523-7
M3 - Article
C2 - 2531826
AN - SCOPUS:0024471492
SN - 0024-3205
VL - 45
SP - 1821
EP - 1829
JO - Life Sciences
JF - Life Sciences
IS - 19
ER -