Receptor antagonists action

Quetiapine. This has a somewhat similar pharmacological profile to clozapine and olanzapine due to its multiple receptor antagonists action. It has been shown to reduce both the positive and negative symptoms of schizophrenia and has a low frequency of extrapyramidal side effects. 

Another problem which can compromise compliance concerns the hypotensive actions of many psychotropic drugs (e.g. tricyclic antidepressants, phenothiazine neuroleptics). Due to the alphaj receptor antagonistic action of these drugs, they are likely to cause severe orthostatic... 

Warner. T.D. er al. (1994) Endothelin receptor antagonists actions and rationale for their development. Biochem. Pharmacol., 48.625-635. 

The P-receptor antagonist action of propafenone is very weak as compared to true antagonists (e.g., propranolol). The plasma concentrations of the drug when used therapeutically are, however, almost 50 times that of propranolol. Thus P-receptor antagonist activity is clinically manifested. 

Jin GZ, Zhu ZT, Fu Y ( ) StephoUdine a potential novel antipsychotic drug with dual D1 receptor agonist and D2 receptor antagonist actions. Trends PharmacoL ScL 2002 23 (l) 4-7. 

Future Outlook for Antidepressants. Third-generation antidepressants are expected to combine superior efficacy and improved safety, but are unlikely to reduce the onset of therapeutic action in depressed patients (179). Many dmgs in clinical development as antidepressive agents focus on estabhshed properties such as inhibition of serotonin, dopamine, and/or noradrenaline reuptake, agonistic or antagonistic action at various serotonin receptor subtypes, presynaptic tt2-adrenoceptor antagonism, or specific monoamine—oxidase type A inhibition. Examples include buspirone (3) (only... 

Dronabinol (tetrahydrocannabinol), the active principle from cannabis and synthetic cannabinoids, nabilone and levonantradol are effective in treating nausea and vomiting in cancer chemotherapy. The mode of action is unclear but appears to involve cannabinoid CBi receptors. Cannabinoids have been shown to reduce acetylcholine release in the cortex and hippocampus, and have been suggested to inhibit medullary activity by a cortical action. Inhibition of prostaglandin synthesis and release of endorphins may also be involved in the antiemetic effect. A review of trials of dronabinol, nabilone or levonantradol concluded that while the cannabinoids were superior to placebo or dopamine receptor antagonists in controlling emesis... 

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