Agonist drugs

Explain what adverse reaction would be more likely to occur in the older adult prescribed a non-ergot dopamine receptor agonist drug. Describe how you would assess for this adverse reaction. 

Corticosteroids, such as beclomethasone (Beclovent), flu-nisolide (AeroBid), and triamcinolone (Azmacort), are given by inhalation and act to decrease the inflammatory process in the airways of the patient with asthma, hi addition, the corticosteroids increase the sensitivity of the p2-receptors. With increased sensitivity of the ( -receptors, the p2-receptor agonist drugs are more effective... 

Ultimately, agonist drugs that directly activate monoamine receptors would appear to be a logical development in this field. Unfortunately, the peripheral side-effects of such compounds could well limit their acceptability even if we were to discover what subset of receptors to target. 

A consequence of a very large receptor reserve for CB1 receptors would be that PET or SPECT could not be used to image the occupancy of the CB1 receptor by biologically significant doses of agonist drugs. This is... 

Agonist drugs can also bind directly to the postsynaptic receptor, so mimicking the physiological effect of the neurotransmitter for example, morphine and heroin bind to the brain s opiate receptors and, thus, directly stimulate feelings of pleasure and pain... 

We have developed chemiluminescent immunoenzymatic assays for (3-ago-nist drugs in the 96-well-microtiter-plate format. Such competitive assays have been used for determination of clenbuterol and of the overall content of p-agonist drugs in the sample. They matched the standard requirements of precision and accuracy, and were more sensitive compared to the conventional colorimetric methods. Moreover, CL detection was very rapid, making these assays suitable for screening analysis. 

Reaction in organic solvent can sometimes provide superior selectivity to that observed in aqueous solution. For example, Keeling et al recently produced enantioenriched a-trifluoromethyl-a-tosyloxymethyl epoxide, a key intermediate in the synthetic route to a series of nonsteroidal glucocorticoid receptor agonist drug candidates, through the enan-tioselective acylation of a prochiral triol using the hpase from Burkholderia cepacia in vinyl butyrate and TBME (Scheme 1.59). In contrast, attempts to access the opposite enantiomer by desymmetrization of the 1,3-diester by lipase-catalysed hydrolysis resulted in rapid hydrolysis to triol under a variety of conditions. 

Dutta AS. Luteinizing hormone-releasing hormone (LHRH) agonists. Drugs Future 1988 13 43-57. 

Fisher A, Barak D Progress and perspectives in new muscarinic agonists. Drug News and Perspective 7[8) 453-464, 1994... 

Kava my also potentiate 5-FITia agonist drugs, thereby suggesting either a direct or indirect serotonergic mechanism of action. Effects on GABA and NMDA are unclear. 

Many of the drugs used in modern anaesthetic practice have an effect on the CT7 and vomiting centre either directly or indirectly, e.g. stimulation of the vestibular apparatus, stimulation of the CTZ by opioid agonist drugs, and an anti-emetic effect of propofol or emetogenic effect of nitrous oxide. Propofol... 

The 32-selective adrenoceptor agonist drugs, particularly albuterol, are the most widely used sympathomimetics for treatment of the bronchoconstriction of asthma at present (Figure 20-4). These agents differ structurally from epinephrine in having a larger... 

Care should be taken not to administer any partial agonist or drug with mixed opioid receptor actions to patients receiving pure agonist drugs because of the unpredictability of both drugs effects reduction of analgesia or precipitation of an explosive abstinence syndrome may result. 

When given in the absence of an agonist drug, these antagonists are almost inert at doses that produce marked antagonism of agonist opioid effects. 

After repeated dosing of animals with p-agonist drugs such as clenbuterol, there is a decrease in both the density of p-receptors in muscle tissue and the stimulation of protein synthesis caused by this drug. 

Research has shown clearly that PPARa is necessary for hepatocarcinogenesis in mice. Thus, the PPARa-agonist drug Wy-14643 causes a 100% incidence of liver tumors in wild-type mice, yet PPARa-null mice are resistant. This has been confirmed using the drug bezafibrate. 

Scopes, D.I. Recent developments in non-peptide kappa receptor agonists, Drug Fut. 1993, 18, 933-947. 

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