Potential dopamine receptor

Emilien G, Maloteaux J-M, Geurts M et al (1999) Dopamine receptors—physiological understanding to therapeutic intervention potential. Pharmacol Ther 84 133-156... 

Psychostimulants. Figure 2 Dopamine molecules have two different possible targets. Both ways are initially increased by DAT inhibition caused by methylphenidate pre- and postsynaptic dopamine receptors. Stimulation of postsynaptic receptors results in inhibition of presynaptic action potential generation. On the other hand, presynaptic receptor stimulation leads to a transmission inhibition of action potentials. Therefore, both mechanisms are responsible for a decrease in vesicular depletion of dopamine into the synaptic cleft (adapted from [2]). 

Low-dose dopamine is not without adverse reactions and most studies have failed to evaluate its potential toxicities. Adverse reactions that may be associated with low-dose dopamine include tachycardia, arrhythmias, myocardial ischemia, depressed respiratory drive, and gut ischemia. Low-dose dopamine has also been postulated to impair resistance to infection through a reduction in prolactin concentrations.21 Furthermore, significant overlap in receptor activation occurs. Therefore, doses considered to activate only dopamine receptors may increase cardiac output and blood pressure through dopamine s effect on 3- or a-adrenergic receptors. 

Aripiprazole was formulated in the early 1980s to function as a potential dopamine modulator, with both antagonist and agonist activity at the D2 receptor. It is the first D2 partial agonist available for the treatment of schizophrenia and is sometimes referred to as a third-generation antipsychotic. This novel mechanism is... 

Anokhin, A.P., Torodov, A.A., Madden, P.A.F., Grant, J.D., Heath, A.C. Brain event-related potentials, dopamine D2 receptor gene polymorphism, and smoking. Genet. Epidemiol. 17(Suppl. 1) S37, 1999. 

In another work, a series of substituted 2-aminoindans was analyzed using MM2-85108. The calculated potential energy surface for rotation around the CH—CH—CH2— N and CH—CH2—N—lp in model compound 70 is presented in Figure 9 and shows 9 minima. These were scrutinized as potential candidates for dopamine receptor agonists, according to several criteria The highest-energy conformation f (Erei = 7.3 kcalmol-1)... 

Giacomelli S, Palmery M, Romanelli L, Cheng CY, Silvestrini B. (1998). Lysergic acid diethylamide (LSD) is a partial agonist of D2 dopaminergic receptors and it potentiates dopamine-mediated prolactin secretion in lactotrophs in vitro. Life Sci. 63(3) 215-22. 

Another potential clinical application of potent, peripherally acting DA agonists is the lowering of intraocular pressure in, for example, glaucoma [18]. There is in vivo and in vitro evidence that dopamine receptors might modulate the intraocular pressure. The influence of both agonists and antagonists for D1 and D2 receptors has been studied. Some human data are also available [19]. 

Dyskinesia Dopamine receptor agonists may potentiate the dopaminergic side effects of levodopa and may cause or exacerbate pre-existing dyskinesia. Decreasing the dose of levodopa may ameliorate this side effect. 

Confusion, hallucinations, delusions, and other psychiatric reactions are potential complications of dopaminergic treatment and are more common and severe with dopamine receptor agonists than with levodopa. Disorders of impulse control may lead to compulsive gambling, shopping, betting, sexual activity, and other behaviors. They clear on withdrawal of the offending medication. 

Zhang A, NeumeyerJL, Baldessarini RJ. Recent progress in development of dopamine receptor subtype-selective agents Potential therapeutics for neurological and psychiatric disorders. Chem Rev 2007 107 274. 

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