Dopamine receptor classification

Clark D, White FJ. Dl receptors—the search for a function a critical evaluation of the D1/D2 dopamine receptor classification and its functional implications. Synapse 1987 1 347-388. 

Table 7.1 Evidence for the initial basic classification of Dj and D2 dopamine receptors...

I. Creese, D. R. Sibley, M. W. Hamblin, S. E. Leff (1983). The classification of dopamine receptors relationship to radioligand binding. Annu. Rev. Neurosci. 6 43-71. 

Duarte EP, Oliveira CR, Carvalho AP (1988) Thermodynamic analysis of antagonist and agonist interaction with dopamine receptors. Eur J Pharmacol 147(2) 227-239 Fredholm BB, Ijzerman AP, Jacobson KA, Klotz KN, Linden J (2001) International Union of Pharmacology. XXV. Nomenclature and classification of adenosine receptors. Pharmacol Rev 53(4) 527—552... 

Table 1 Tissues in which neurotransmitter release is increased (f) or decreased (J.) by presynaptic dopamine receptor activation. Receptor classification (except with superscript11) as by the authors cited. Designation as D -like or D2-like where no differentiation between D and D5, or between D2, D3 and D4, was made...

There is much ambiguity in the currently used classifications of dopamine receptors. This complexity is partly due to the combined use of a classification based on binding data (67, 68) and... 

Figure 4. Representation of the classification of the dopamine receptor based on its coupling with adenylate cyclase activity. DA+ receptors (left) are coupled to adenylate cyclase through the Ns GTP-binding protein (91) with secondary activation of adenylate cyclase. DA. receptors (middle) are coupled through the Ni GTP-binding protein, thus resulting in inhibition of cyclic AMP formation. DA0 receptors (right) are those uncoupled to cyclic AMP formation, the example being possibly some autoreceptors on nigrostriatal dopaminergic neurons.

Commentary Utility and Problems in the Classification of Dopamine Receptors... 

In their communication the evidence is summarized suggesting two distinct types of dopamine receptors in the periphery, designated DA] and DA2. Goldberg and Kohli s classification is based primarily on in vivo results using the vasculature and flow of blood to the renal, femoral and other selected... 

Four Major Reasons for Problems in the Classification and Identification of Dopamine Receptors in the Periphery... 

Dopamine induces biochemical and physiological effects in the mammalian neostriatum. The occurrence of a D-l dopamine receptor (in the classification scheme of Kebabian and Caine) accounts for the ability of dopamine to enhance cyclic AMP formation. The occurrence of a D-2 dopamine receptor accounts for the ability of dopamine to inhibit cyclic AMP formation brought about by stimulation of a D-l dopamine receptor. Dopamine receptors mediate the regulation of (1) the release or turnover of acetylcholine (postsynaptic dopamine receptor) and (2) the release or turnover of dopar mine (presynaptic autoreceptor). Both receptors can be classified as D-2 dopamine receptors. Indications for the occurrence of dopamine receptors affecting the release or turnover of GABA, glutamate, serotonin and several neuropeptides are evaluated. 

The classification of dopamine receptors. Although Kebabian and Caine Q) performed an excellent service to the scientific community in proposing the D-l and D-2 receptor hypothesis, this remains to be proven by isolating and characterizing these receptors. These have been excellently reviewed by Cronin (2). Indeed the statement that the "D" receptors of the anterior pituitary are independent of adenylate cyclase is incorrect. We (3) and others (4, ) have shown a consistant and specific inhibitory relationship of the anterior pituitary dopamine receptor and adenylate cyclase. 

Dopamine receptors were first classified into Di and D, subtypes (530). As a testament to the validity of this initial classification, the five subsequently cloned dopamine receptors fall into structural and functional groupings commensurate with the or D, subtypes. 

Antipsychotic drugs A major classification of drugs, most of which are dopamine receptor antagonists (with the exception of the newer antipsychotic medications), and are used to address disturbances in affect and mood such as psychosis, delusions, and psychotic depression. 

Neuropharmacologic classification of addictive drugs by primary target (see text and Table 32-1). DA, dopamine GABA, 7-aminobutyric acid GHB, 7-hydroxybutyric acid GPCRs, G protein-coupled receptors THC, A9-tetrahydrocannabinol. 

No recognised classification system exists for atypical antipsychotics.Tentative terms based on receptor binding profiles have been applied to certain drug groupings.for example broad spectrum atypicals for clozapine, olanzapine and quetiapine. whilst risperidone and ziprasidone have been described as high affinity serotonin-dopamine antagonists . 

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