TY - JOUR
T1 - Regional variations in binding capacities at μ-, δ- and κ-opioid sites in membrane suspensions from rabbit brain
AU - Petrillo, Paola
AU - La Regina, Antonio
AU - Sbacchi, Massimo
AU - Tavani, Alessandra
AU - Robson, Linda E.
AU - Kosterlitz, Hans W.
PY - 1989/7/18
Y1 - 1989/7/18
N2 - The highest maximum binding capacities at the μ-sites of rabbit brain are in the striatum, with intermediate levels in the diencephalon, mesencephalon, cerebellum and cortex and low level in the pons-medulla and hippocampus. For the δ-site the highest maximum binding capacity is also in the striatum; there are almost equally low levels in the other brain regions. At the κ-sites the maximum binding capacities are highest in the diencephalon; there are intermediate levels in the cortex and striatum, and low levels in the mesencephalon, cerebellum, hippocampus and pons-medulla. The KD values lack reproducibility; there are no regional variations at the κ-site as estimated with [3H](-)-bremazocine, but the possibility cannot be excluded that there are regional variations in the KD values for [3H][D-Ala2, MePhe4, Gly-ol5]enkephalin at the μ-site or for [3H][D-Ala2,D-Leu5]enkephalin at the δ-site. It may be important to use saturation analysis in future investigations of the distributions of the binding sites.
AB - The highest maximum binding capacities at the μ-sites of rabbit brain are in the striatum, with intermediate levels in the diencephalon, mesencephalon, cerebellum and cortex and low level in the pons-medulla and hippocampus. For the δ-site the highest maximum binding capacity is also in the striatum; there are almost equally low levels in the other brain regions. At the κ-sites the maximum binding capacities are highest in the diencephalon; there are intermediate levels in the cortex and striatum, and low levels in the mesencephalon, cerebellum, hippocampus and pons-medulla. The KD values lack reproducibility; there are no regional variations at the κ-site as estimated with [3H](-)-bremazocine, but the possibility cannot be excluded that there are regional variations in the KD values for [3H][D-Ala2, MePhe4, Gly-ol5]enkephalin at the μ-site or for [3H][D-Ala2,D-Leu5]enkephalin at the δ-site. It may be important to use saturation analysis in future investigations of the distributions of the binding sites.
KW - (Binding capacities
KW - Binding affinities
KW - Brain regions
KW - Rabbit
KW - δ-
KW - κ-Opioid binding sites
KW - μ-
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U2 - 10.1016/0014-2999(89)90061-7
DO - 10.1016/0014-2999(89)90061-7
M3 - Article
C2 - 2551699
AN - SCOPUS:0024348076
VL - 166
SP - 213
EP - 217
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
SN - 0014-2999
IS - 2
ER -