Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Dopamine receptors drugs acting

The exact mechanism of action of these dm is not understood. It is thought that these drug s act directly on postsynaptic dopamine receptors of nerve cells in the brain, mimicking die effects of dopamine in the brain. [Pg.269]

Dopamine receptor blocking agents. Many of the neuroleptics used in the treatment of schizophrenia frequently produce parkinsonian symptoms as unwanted effects. Neuroleptics block dopamine receptors and their therapeutic effect seems to be related to this action. Although these drugs act on DA systems without distinction, some are more selective. Thioridazine, clozapine and molindone, for example, have electrophysiological effects in the limbic region of the brain but little action in the nigro-striatal area. This selectivity may be related to receptor subtype specificity (see Chs 12 and 54). [Pg.777]

Dopamine activity can be enhanced in one of four main ways. Medications can stimulate dopaminergic nerve cells to release dopamine into the synapse. This is the way that stimulants such as methylphenidate (Ritalin), dextroamphetamine (Dexe-drine), and dextroamphetamine/amphetamine (Adderall) work. In addition, certain drugs of abuse, notably cocaine and methamphetamine, act in part in this way. Providing more of the raw material that nerve cells use to manufacture dopamine can also increase dopamine activity. This is the approach that neurologists use when they prescribe L-DOPA (Sinemet) to patients with Parkinson s disease. Nerve cells convert L-DOPA into dopamine. L-DOPA otherwise has little place in the treatment of psychiatric disorders. Dopamine activity can also be increased by medications that directly stimulate dopamine receptors. Bromocriptine, another medication used to... [Pg.363]

Drugs that are successful in treating the disease act as dopamine receptor blockers and are known as antipsychot-ics or neuroleptics (e.g. chlorpromazine, haloperidol). Antipsychotic drags reduce some of the symptoms, especially the delusions and hallucinations. A side-effect of the drugs is that they can result in symptoms similar to those seen in patients with Parkinson s disease. This is not surprising, since the hypothesis to explain Parkinson s disease is too low a concentration of dopamine in a specific area of the brain (see below). [Pg.320]

B. Apomorphine is an older drug with dopamine receptor agonist properties. It acts both centrally and peripherally. It is not contraindicated in cases of BPH but rather may be the drug of choice in this instance. [Pg.740]

The large majority of antipsychotic drugs act mainly as dopamine receptor antagonists reducing the excess responsiveness to that neurotransmitter present in psychoses. It was found a decade ago that antagonists of serotonin H2 showed promising antipsychotic activity in several model systems. These dmgs would be better tolerated than their predecessor since they should be devoid of side effects... [Pg.370]

The side effects frequently observed on prolonged use of antipsychotic drugs that act on dopamine receptors have been ascribed to indiscriminate antagonism at sites... [Pg.395]

Dopamine is a major neurotransmitter which acts on multiple receptors. It can activate both a and 3 adrenoceptors in addition to acting on specific dopamine receptors. These are widely distributed throughout the CNS and are also present in the renal tubules and renal and mesentric blood vessels, and many dopaminergic drugs are used in the treatment of Parkinson s disease, psychiatric disorders, as antiemetics, and for renal protection. Neuroleptic drugs, such as haloperidol and droperidol, are dopamine receptor antagonists. [Pg.28]

FIGURE 11 — 2. The dopamine receptor antagonist hypothesis of antipsychotic drug action for positive symptoms of psychosis in the mesolimbic dopamine pathway is shown here. Blockade of postsynaptic dopamine 2 receptors by a dopamine 2 antagonist acting in the mesolimbic dopamine pathway is hypothesized to mediate the antipsychotic efficacy of the antipsychotic drugs and their ability to diminish or block positive symptoms. [Pg.403]

FIGURE 8-1 Effects of antipsychotic drugs on dopamine synapses. Antipsychotics act as postsynaptic receptor antagonists to block the effects of overactive dopamine transmission. [Pg.94]

Bracco F, Battaglia A, Chouza C, et al. The long-acting dopamine receptor agonist cabergohne in early Parkinson s disease final results of a 5-year, doubleblind, levodopa-controlled study. CNS Drugs. 2004 18 733-746. [Pg.132]

The receptors for these hormones are typical seven-transmembrane-domain serpentine peptides (see Chapter 2 Drug Receptors Pharmacodynamics). Each hormone acts as a ligand within a receptor pocket, inducing conformational activating changes in the receptor. The conformational changes in the receptor s intracellular third loop and carboxyl terminal tail activate an adjacent intracellular G protein. The Gm protein is associated with the receptors for GnRH and TRH, G with the dopamine receptor, and Gs protein with the receptors for the other hormones listed above. [Pg.851]


See other pages where Dopamine receptors drugs acting is mentioned: [Pg.105]    [Pg.211]    [Pg.1174]    [Pg.294]    [Pg.550]    [Pg.153]    [Pg.161]    [Pg.222]    [Pg.949]    [Pg.178]    [Pg.78]    [Pg.78]    [Pg.298]    [Pg.135]    [Pg.830]    [Pg.678]    [Pg.691]    [Pg.737]    [Pg.224]    [Pg.533]    [Pg.197]    [Pg.607]    [Pg.626]    [Pg.245]    [Pg.1796]    [Pg.509]    [Pg.280]    [Pg.362]    [Pg.126]    [Pg.199]    [Pg.641]    [Pg.659]    [Pg.724]    [Pg.421]    [Pg.561]   
See also in sourсe #XX -- [ Pg.362 ]




SEARCH



Dopamine receptor

Drug-receptor

Drugs acting

© 2024 chempedia.info