Imidazoline subtypes

Arnsten AFT, Leslie FM (1991) Behavioural and receptor binding analysis of the Oj-agonist, UK-14304 (5 bromo-6 (2-imidazoline-2-yl amino) quinoxaline) evidence for cognitive enhancement at an a -adrenoceptor subtype. Neuropharmacology 30 1279-1289... 

Horie K, Obika K, Foglar R, Tsujimoto G. Selectivity of the imidazoline a-adrenoceptor agonists (oxymetazoline and cirazoline) for human cloned a,-adrenoceptor subtypes. Br J Pharmacol 1995 116 1611-1618. 

Clonidine [ban, inn, usan] (clonidine hydrochloride [inn. usan] Catapres Dixarit ) is an imidazoline derivative, a (selective a2-subtype) o-adrenoceptor agonist. It can be used (orally or transdermally) as an antihypertensive (probably acting within the CNS). It has formerly been used in ANTIMIGRAINE prophylaxis, clonidine hydrochloride clonidine. 

Since imidazoline receptors are sub-classified, it is generally assumed that tritiated clonidine labels Ii-subtype of imidazoline binding sites while tritiated idazoxan is a useful tool to label l2-binding sites in this case, it is however necessary to check whether these sites are insensitive to unlabelled clonidine [20]. In order to investigate these latter sites a tritiated form of a more selective... 

It has also been proposed that the terminals of sympathetic neurons supplying cardiovascular tissue express a non-U, non-U subtype of the putative imidazoline receptor that is both CBi receptor-like and a2-adrenoceptor-like and that mediates inhibition of evoked noradrenaline release when activated (reviewed in... 

A vast array of structurally unrelated compounds interacts with a I-adrenoreceptor subtypes, which makes it inherently difficult to determine the structural requirements leading to receptor subtypes selectivity (Ruffolo et al., 1995 Leonard et al., 1996 Kenny et al., 1997). The majority of a,-adrenoreceptor antagonists displays a competitive mechanism of action and belongs to a variety of different structural classes such as yohimbanes, ergot alkaloids, quinazolines, A-arylpiperazines, imidazolines, phenylalkylamines, benzodioxanes, indoles, 1,4-dihydro-pyridines, hetero-fused 3-benzazepines, dibenzoquino-lizines. 

Brown, C.M., MacKinnon, A.C., McGrath, J.C., Spedding, M. and Kilpatrick, A.T. (1990) 2-Adrenoceptor subtypes and imidazoline-like binding sites in the rat hrain. 

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