Big Chemical Encyclopedia

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

Articles Figures Tables About

Opioid receptor affinities determination

Prior to cloning of the opioid receptors, affinity for these receptors was most commonly determined by the use of homogenates or membrane fractions from rat, guinea pig, or mouse brain, which contain all three types of opioid receptors. The relative amounts of different opioid receptor types vary between species, however, particularly for k receptors. In rat brain k opioid receptors constitute only about 10-15% of the total number of opioid receptor sites (124), whereas in species such as guinea pig they represent approximately 30% of the total opioid receptor population (125). Over 80% of the opioid receptors in the guinea pig cerebellum are k receptors (126), so this tissue was frequently used in K-receptor bind-... [Pg.347]

When the efficacy of biphalin-stimulated G protein activation was examined (Table 3) in delta opioid receptor-transfected CHO cells, an efficacy ratio of 0.42 was determined as compared with deltorphin-II and DPDPE, the latter a reference delta-selective agonist. Such low efficacy values suggest that biphalin does not efficiently stimulate the G protein through the delta receptor [9]. Relative affinities of biphalin and morphine for mu, delta, and kappa binding sites in guinea pig brain membranes are shown in Table 4. [Pg.248]

These discoveries were followed by the isolation of cDNA for two opioid receptors derived from rat brain, identified as ROR-A and ROR-B [55], Competition studies performed with DSLET, DPDPE, and DAMGO in transfected CHO cells determined that the ROR-A corresponds to the 6-opioid receptor and ROR-B corresponds to the p-opioid receptor [55]. Finally, human cDNA for the 6-opioid was expressed in COS-7 cells [56]. Again, competition studies confirmed the presence of the 6-opioid receptor. Moreover, it was determined that the cloned receptor represents the 62-opioid receptor, since NTB showed an approximately eightfold greater affinity than BNTX [56]. The molecular biology of the cloned opioid receptors has since been reviewed [57]. It has been subsequently determined that the cloned 6-opioid receptor may correspond to the 62-isoform [57]. [Pg.302]

The simplified SNC 80 structure 17 was further modified by replacement of the N-l of the piperazine with carbon double bond, leading to a new series of diarylalk-enylpiperidines [49]. These new compounds were evaluated for their affinity for all three human opioid receptors and their agonist activity was determined using the... [Pg.129]

The receptor selectivity for antinociception produced by (- )cyclorphan and MCL-101 in the writhing test was also determined. (- )Cyclorphan produced antinociception that was mediated by k and 8 opioid receptors. In contrast, MCL-101 produced antinociception that was mediated by K and p receptors, which is in agreement with the results from the tail flick assay. The receptor selectivity results in the writhing assay correlated with the binding results in Table 1, which showed that (- )cyclorphan had a higher affinity than MCL-101 for the 8 receptor. [Pg.273]

Sagan, S., Amiche, S., Delfour, A., Mor, A., Camus, A. and Nicolas, P. 1989, Molecular determinants of receptor affinity and selectivity of the natural delta-opioid agonist, demienkephalin. Journal of Biological Chemistry 264, 17100-17160. [Pg.402]

Racemic benzofuro[2,3-c]pyridin-6-ols have been found that have high affinity for mu-opioid receptors (Hutchison et al., 1989). In order to pursue our study of the topological characteristics of mu-opioid ligands, we have begun to determine the configuration of the optically pure benzofuro[2,3-c]pyridine-6-0I that is responsible for the high affinity. We have now synthesized a series of optically pure... [Pg.101]

Lactam 36 was the first cyclic enkephalin analog prepared. It has a higher affinity for the p-opioid receptor than for the 8-receptor. The methylamine-bridged enkephalin (MABE) analog 37 exhibits nanomolar affinity for isolated p- and 8-receptors and in an in vivo (rat) thermal escape assay an ED50 of 0.027 pg was determined, as compared with an ED50 of 2.4 pg for morphine. ... [Pg.317]


See other pages where Opioid receptor affinities determination is mentioned: [Pg.257]    [Pg.76]    [Pg.125]    [Pg.814]    [Pg.76]    [Pg.125]    [Pg.144]    [Pg.212]    [Pg.57]    [Pg.390]    [Pg.207]    [Pg.17]    [Pg.47]    [Pg.73]    [Pg.194]    [Pg.272]    [Pg.315]    [Pg.320]    [Pg.385]    [Pg.186]    [Pg.96]    [Pg.97]    [Pg.233]    [Pg.447]    [Pg.105]    [Pg.128]    [Pg.310]    [Pg.87]    [Pg.485]    [Pg.976]    [Pg.69]    [Pg.105]    [Pg.128]    [Pg.248]    [Pg.151]    [Pg.207]    [Pg.87]    [Pg.102]    [Pg.1983]   
See also in sourсe #XX -- [ Pg.30 , Pg.814 ]

See also in sourсe #XX -- [ Pg.814 ]




SEARCH



Affinity Determination

Opioid receptor affinities

Opioid receptors

Opioids receptors

Receptor affinity

© 2024 chempedia.info