Topic
Imiloxan
About: Imiloxan is a research topic. Over the lifetime, 48 publications have been published within this topic receiving 1229 citations.
Papers
Journal Article•
TL;DR: Two distinct pharmacological profiles for the two alpha-2 adrenergic receptor subtypes in several different tissues are demonstrated, further support the existence and definition of these subtypes.
Abstract: The affinities of 34 adrenergic antagonists for alpha-2 adrenergic receptors were determined from homogenate radioligand binding studies using [3H]yohimbine and [3H]rauwolscine. It has been suggested that alpha-2 adrenergic receptors can be subdivided into alpha-2A and alpha-2B subtypes. Oxymetazoline is selective for alpha-2A receptors, whereas prazosin is alpha-2B selective. Five different tissues were used, each of which has only one of the two subtypes: human platelet (alpha-2A), HT29 cell line (alpha-2A), human cerebral cortex (alpha-2A), neonatal rat lung (alpha-2B), and NG108-15 cell line (alpha-2B). The drug affinities were highly correlated when alpha-2A tissues were compared with alpha-2A tissues (r = 0.97 to 0.98) or when the two alpha-2B tissues were compared (r = 0.99). By contrast, comparison of an alpha-2A tissue with an alpha-2B tissue resulted in poor correlations (r = 0.77 to -0.87). Three new subtype selective drugs were identified among these drugs on the basis of at least a 10-fold greater affinity for one subtype. All three were selective for the alpha-2B subtype: ARC-239 (100-fold selective), chlorpromazine (18-fold selective), and 7-hydroxychlorpromazine (17-fold selective). These studies, by demonstrating distinct pharmacological profiles for the two alpha-2 adrenergic receptor subtypes in several different tissues, further support the existence and definition of these subtypes. The identification of a cell line for each subtype should be useful in the further study of alpha-2 adrenergic receptor subtypes.
322 citations
TL;DR: It is hypothesized that the alpha 2 adrenoceptor subtype alpha 2A is involved in the antinociception of spinal clonidine and dexmedetomidine, and alpha 2B is involvedIn that of ST-91.
93 citations
TL;DR: Data support the involvement of alpha 2-adrenoceptors in the regulation of male sexual behavior, specifically by facilitating sexual arousal, with no effects on ejaculatory threshold, as measured by intromission frequency.
77 citations
TL;DR: Deep, largely inhibitory effects of these agents were demonstrated at dose ranges which have been shown to enhance sexual arousal, indicating that within the nervous system alpha 2-adrenoceptor antagonists can modulate erectile and ejaculatory mechanisms quite independently from effects on arousal/motivation.
57 citations
TL;DR: Imiloxan was identified as a selective α2B ligand while benoxathian displayed a high degree of selectivity for the α2A‐adrenoceptor binding site, which should make it a valuable tool in the classification of α2‐ad Renoceptor subtypes.
Abstract: 1. The alpha 2-adrenoceptor binding sites of rabbit spleen and rat kidney, labelled with [3H]-rauwolscine, were characterized using a range of subtype selective ligands. 2. In rabbit spleen, the alpha-2-adrenoceptor binding sites displayed high affinity for oxymetazoline and WB 4101 and low affinity for prazosin and chlorpromazine suggesting the presence of an alpha 2A subtype. 3. There was evidence for heterogeneity of the alpha 2-adrenoceptor binding sites present in rabbit spleen. The results obtained with oxymetazoline and WB 4101 indicated that at least 75% of the [3H]-rauwolscine binding sites in this preparation displayed a pharmacology consistent with the presence of an alpha 2A subtype. 4. In rat kidney, the alpha 2-adrenoceptor binding sites displayed high affinity for prazosin and chlorpromazine and low affinity for oxymetazoline and WB 4101 suggesting the presence of an alpha 2B subtype. 5. The inclusion of guanylylimidodiphosphate (Gpp(NH)p, 0.1 mM) did not modify the pharmacology of the alpha 2-adrenoceptor binding sites present in the two preparations. Furthermore, when the two membrane preparations were combined, the resultant pharmacology was still consistent with the presence of two receptors that retained the characteristics of the alpha 2A and alpha 2B subtypes. 6. Imiloxan was identified as a selective alpha 2B ligand while benoxathian displayed a high degree of selectivity for the alpha 2A-adrenoceptor binding site. The selectivity of imiloxan for the alpha 2B-adrenoceptor binding site, coupled with its specificity for alpha 2-adrenoceptors, should make it a valuable tool in the classification of alpha 2-adrenoceptor subtypes.
53 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2017 | 2 |
| 2016 | 4 |
| 2015 | 4 |
| 2014 | 1 |
| 2013 | 5 |
| 2012 | 2 |