Characterization of Central α-Adrenoceptors Using H-Clonidine and Its Derivatives

Abstract

α-adrenoceptors in brain can be studied readily by radioligand binding techniques. This provides valuable information not only on the distribution of receptors in brain regions, but also on the regulation of receptors. The usefulness of this technique is dependent in part on a radioligand with high specificity for the receptor under study. Our studies have shown that 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-clonidine does not bind exclusively to α-adrenoceptor subtypes, but also interacts with α-adrenoceptors. In contrast, 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-guanfacine labels a high affinity α2 subtype with good selectivity, but 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-lofexidine probably labels with both α2 and α1-adrenoceptor binding sites. α-adrenoceptors in brain can be studied readily by radioligand binding techniques. This provides valuable information not only on the distribution of receptors in brain regions, but also on the regulation of receptors. The usefulness of this technique is dependent in part on a radioligand with high specificity for the receptor under study. Our studies have shown that 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-clonidine does not bind exclusively to α-adrenoceptor subtypes, but also interacts with α-adrenoceptors. In contrast, 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-guanfacine labels a high affinity α2 subtype with good selectivity, but 3 Rouot BM U’Prichard DC Snyder SH Multiple α2-noradrenergic receptor sites in rat brain: selective regulation of high affinity [3H] clonidine binding by guanyl nucleotides and divalent cations. J Neurochem. 1980; 34: 374-384 Crossref PubMed Scopus (115) Google Scholar H-lofexidine probably labels with both α2 and α1-adrenoceptor binding sites.