Binding profile of trazodone and dapiprazole to some brain receptors.
Trazodone and dapiprazole displace ligands binding to rat brain alpha-1 adrenoceptors. The displacement of 3H-ligands to alpha-2, serotonin1 (5-HT1), dopamine, beta and opiate receptors is either absent or takes place at relatively higher concentrations. Trazodone, unlike dapiprazole, also inhibits binding to serotonin2 (5-HT2) receptors. Some pharmacological effects show a satisfactory correlation with these data. The psychopharmacological effects of trazodone and dapiprazole are similar, whereas the binding inhibition to 5-HT2 receptors is different, which would indicate that the psychopharmacological effects do not primarily depend on these receptors. The displacement of the binding to alpha-1 adrenoceptors by dapiprazole has a time course similar to that of its brain concentrations as well as to that of sedative and alpha-blocking effects. Dapiprazole and trazodone have antinociceptive effects and inhibit the binding to opiate receptors, although at relatively high concentrations.
Valeri
P
P
Institute of Pharmacology and Pharmacognosy, University of Rome La Sapienza, Italy.
Palmery
M
M
Silvestrini
B
B
D000818:Animals; D001921:Brain / Q000378:metabolism*; D008297:Male; D010879:Piperazines; D051381:Rats; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects / Q000378:metabolism*; D011954:Receptors, Dopamine / Q000187:drug effects / Q000378:metabolism; D011957:Receptors, Opioid / Q000378:metabolism; D011985:Receptors, Serotonin / Q000187:drug effects / Q000378:metabolism*; D014196:Trazodone / Q000378:metabolism* / Q000494:pharmacology; D014230:Triazoles / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology
D010879:Piperazines; D011942:Receptors, Adrenergic, alpha; D011954:Receptors, Dopamine; D011957:Receptors, Opioid; D011985:Receptors, Serotonin; D014230:Triazoles; C035289:dapiprazole; D014196:Trazodone