Wang S S, Mathis C A, Peroutka S J
Department of Neurology, Stanford University, CA 94305.
Psychopharmacology (Berl). 1988;94(3):431-2. doi: 10.1007/BF00174703.
R(-)-2,5-Dimethoxy-4-77Br-amphetamine [77Br-R(-)DOB], a radioligand of high specific activity (1500 +/- 200 Ci/mmol), was used to label membrane-associated recognition sites in rat brain. 77Br-R(-)DOB sites were of high affinity (KD = 0.19 nM) but low density (Bmax = 0.32 pmol/g tissue) in rat brain preparations. Competition experiments show that both 5-hydroxytryptamine (5-HT) and 5-HT2 antagonists display nanomolar potency for these sites. We conclude that 77Br-R(-)DOB labels 5-HT recognition sites in rat brain which do not fit into current classifications of 5-HT binding subtypes. This finding may be of aid in deciphering the mechanism of action of hallucinogens in man.
