Serotonin agonists activity

Antipsychotics (conventional agents have nonspecific dopamine receptor antagonsim atypical agents also have serotonin antagonist activity), ecopipam, GBR-12909 and other partial dopamine agonists (may be functional antagonists)... 

COMMENT I am not sure the serotonin is inhibitory and dopamine excitatory is all that naive. There were clinical studies published where they showed that serotonin agonists could completely suppress the CNS stimulant effects of amphetamine clinically in humans. So you may be seeing the same thing. I am not sure that it has to be a psychedelic activity superimposed. It may simply be some kind of a synergistic attenuation. 

Mechanism of Action An antipsychotic agent that provides partial agonist activity at dopamine and serotonin (S-HTj ) receptors and antagonist activity at serotonin (5-HTja) receptors. Therapeutic Effect Diminishes schizophrenic behavior. Pharmacokinetics Well absorbed through the GI tract. Protein binding 99% (primarily albumin). Reaches steady levels in 2 wk. Metabolized in the liver. Eliminated primarily in feces and, to a lesser extent, in urine. Not removed by hemodialysis. Half-life 75 hr. 

Trazodone is a triazolopyridine derivative, with relatively weak serotonin reuptake inhibition. Trazodone also has antagonist activity at 5-HTia and 5-HTic sites (Haria et ah, 1994). Trazodone s active metabolite, m-CPP, serves as a direct serotonin agonist. 

To date, the only serotonergic agonist that was associated with the provocation of brief exacerbations of OCD symptoms in some studies is mCPP, which possesses only weak affinity for dopamine, acetylcholine, and a,-adrenergic and (i-adrenergic receptors [Hamik and Peroutka 1989). The agonistic activity of mCPP is greatest for the 5-hydroxytryptamine [5-HT serotonin] S-HTjc and S-HTj receptor subtypes and to a lesser extent to the 5-HT, and 5-HTjp subtypes [Barr et al. 1992]. 

Ramelteon is a hypnotic with melatonin receptor agonist activity targeting melatonin MTj and MT2 receptors. It has not been proven to induce dependence. As with zolpidem and zaleplon, no known anxiolytic properties have been elicited. No appreciable activity on serotonin, dopamine, GABA, or acetylcholine is present with the parent compound, but in vitro studies report that its primary metabolite M-II has weak 5-HT2g receptor agonist activity. 

In contrast, Bach et al (27) reported that the pyrazole derivative (LY 141865) is devoid of alpha and serotonin agonist and antagonist effects. Preliminary studies in our laboratories demonstrated that LY 141865 is a potent DA2 agonist without alpha-adrenergic or DAj activity. 

The (i-carbolinc skeleton with its 9H-pyrido[ 3,4-fr ]indole (29) is frequently encountered in pharmacology due to its activity in the central nervous system at serotonin receptors. It also shows prominent biological properties at the benzodiazepine receptor (BzR) [45]. ZK 93423 (30) remarkably amplifies the agonist activity of such compounds towards BzR. 1,2,3>9-Telrahydro-(>-carbolines are common precursors of (i-carbolines [46]. 1,3.4,9-Tetrahydro-... 

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