Dopamine, agonist

The task of the study presented here was to separate a data set of 172 molecules into benzodiazepine agonists 60 compounds) and dopamine agonists (112 compounds) [84]. 

To illustrate this point, Figure 10.4-10 shows the contents of the neuron at position (4,10) (see Figure 10.4-9). This neuron obtained two dopamine agonists and. 

The ergolines have provided a number of drugs that show interaction with neurotransmitters. Depending on the substitution pattern, they may be dopamine agonists or antagonists, a-adrenergic blockers, or Inhibitors of the release of prolactin. A recent member of the series, pergolide... 

FIGURE 5.1 Ratio of affinity (open circles) and agonist potency (filled circles) for dopamine agonists on dopamine D2 vs D3 receptors. Abscissae numbers referring to agonist key on right. Data calculated from [1],... 

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)... 

Figure 7.6 Chemical structures of some dopamine agonists and antagonists...

Figure 15.5 Counteracting the emetic effect of (a) levodopa and (b) a dopamine agonist in the therapy of PD.

Treseder, SA, Jackson, M and Jenner, P (2000) The effects of central aromatic amino acid (dopa) decarbosylase inhibition on the motor actions of L-dopa and dopamine agonists in MPTP-treated primates. Brit. J. Pharmacol. 129 1355-1366. 

Maeda, H. Sato, T. and Maki, S. Effects of dopamine agonists on hypothalamic defensive attack in cats. Physiol Behav 35 89-92, 1985. 

ANSWER I think it is very clear that there is a population of autoreceptors at the axonal end, but there is no population of autoreceptors in the axon that passes through the medial forebrain level. The antidromic stimulation is up there, and it looks as if amphetamine and related dopamine agonists cause a decrease in excitability of the terminal field in the same way that they cause a decrease in excitability in the cell body. 

QUESTION How do you imagine that both a receptor antagonist and an uptake inhibitor would block the effects It would seem that if dopamine is involved, it would either be acting on a membrane receptor or inside, but not both. I would also like to ask a more specific question. You showed that the alpha MT protected effect could be reversed by dopa. And I think you imagined that that was because of dopamine formation. But have you tried dopamine agonists to see if they would antagonize either the protective effect of alpha methyltyrosine or, particularly, the protective effect of the dopamine antagonists to try to verily that those protective effects really have to do with blockade of a dopamine receptor as opposed to some other possibility ... 

Bannon, M.J. Elliot, PJ. and Bunny, E.B. Striatal tachykinin biosynthesis Regulation of mRNA and peptide levels by dopamine agonists and antagonists. Mol Brain Res 3 31-37, 1987. 

Ellinwood, E.H., Jr., and Kilbey, M.M. Alteration in motor frequencies with dopamine agonists and antagonists. Psychopharmacol Bull 15 49-50, 1979. 

A number of azetidine-based compounds have been disclosed in patent applications from Aventis Pharma for CBi-modulated treatment of diseases such as obesity, Parkinson s disease, schizophrenia, respiratory and neurological diseases [330-334]. Compound (556) was specifically claimed for use in two formulation patent applications [330, 331] for a stable semi-solid composition and oral emulsion composition, respectively. The optional coadministration of an agent that activates norepinephrinergic and se-rotoninergic neurotransmission (for example, sibutramine) or dopaminergic neurotransmission was also claimed for the treatment of obesity. The optional use of a dopamine agonist (for example, levodopa) was claimed... 

Opioids, benzodiazepines, barbiturates, corticosteroids, dopamine agonists (e.g., amantadine, bromocriptine, levodopa, pergolide, pramipexole, ropinirole), H2-receptor antagonists, anticholinergics (e.g., diphenhydramine, trihexylphenidyl), P-adrenergic blockers, clonidine, methyldopa, carbamazepine, phenytoin, baclofen, cyclobenzaprine, lithium, antidepressants (e.g., tricyclic antidepressants, selective serotonin reuptake inhibitors), and interleukin-2... 

Dopamine agonists are useful as initial therapy, as they can delay the need to start levodopa and can decrease the risk of developing motor fluctuations by two- to threefold during the first 4 to 5 years of treatment. After a few years, dopamine agonists inadequately control the patient s symptoms and levodopa needs to be started. In advanced disease, dopamine agonists can be added to levodopa because they have a longer duration of action, minimize fluctuations in dopamine blood concentrations, decrease off-time, improve wearing-off symptoms, allow a reduction in levodopa dose, and improve ADLs.1-3,16,22,23,26... 

Add other PD medications (dopamine agonist, selegiline, amantadine, or COMT inhibitor)... 

Rescue with a dopamine agonist (apomorphine) given with domperidone or trimethobenzamide... 

Add Sinemet CR or dopamine agonist at bedtime if having nighttime offs... 

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