Selective labelling of high affinity 5-hydroxytryptamine1 receptors in whole rat brain.
In synaptic membranes prepared from whole rat brain, cinanserin produced a relatively shallow inhibition curve of [3H] 5-HT binding with Hill slope of 0.68, as compared with that observed in the [3H]spiperone binding (Hill slope = 0.99). Furthermore, nonlinear regression analysis demonstrated that the former inhibition curve is best fitted by a two-site model. Regional and Scatchard analyses both clearly revealed that, in rat brain, at least two populations of binding sites were labelled by [3H]5-HT; however, high affinity binding sites (K(D) = 1.90 nM, Bmax = 0.188 pmoles/mg protein) could apparently be differentiated from the others by the action of 5 nM cinanserin.
D000818:Animals; D001921:Brain / Q000378:metabolism*; D001931:Brain Mapping; D002928:Cinanserin / Q000494:pharmacology*; D002934:Cinnamates / Q000494:pharmacology*; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011985:Receptors, Serotonin / Q000378:metabolism*; D013134:Spiperone / Q000378:metabolism; D013570:Synaptic Membranes / Q000378:metabolism
D002934:Cinnamates; D011985:Receptors, Serotonin; D013134:Spiperone; D002928:Cinanserin