Differential effects of selective alpha 1- and alpha 2-adrenoceptor agonists on intraocular pressure in the conscious rabbit.
In the present study the influence of topically applied selective alpha 1- and alpha 2-adrenoceptor agonists on intraocular pressure and the diameter of the pupil was investigated in conscious rabbits. Selective stimulation of the alpha 1-subtype of receptors induced an elevation in intraocular pressure, accompanied by mydriasis, whereas stimulation of the alpha 2-subtype caused a marked and dose-dependent ocular hypotensive response, which could be blocked by the selective alpha 2-adrenoceptor antagonist yohimbine. After application of the non-selective alpha-adrenoceptor agonist clonidine the alpha 2-adrenoceptor mediated decrease in IOP is probably counteracted by a pressor effect due to the stimulation of alpha 1-adrenoceptors.
D000316:Adrenergic alpha-Agonists / Q000494:pharmacology*; D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001381:Azepines / Q000494:pharmacology; D003000:Clonidine / Q000031:analogs & derivatives / Q000494:pharmacology; D005260:Female; D007429:Intraocular Pressure / Q000187:drug effects*; D008297:Male; D010656:Phenylephrine / Q000494:pharmacology; D011343:Procaine / Q000031:analogs & derivatives / Q000494:pharmacology; D011680:Pupil / Q000187:drug effects*; D015016:Yohimbine / Q000494:pharmacology
D000316:Adrenergic alpha-Agonists; D000317:Adrenergic alpha-Antagonists; D001381:Azepines; C030655:St 587; D010656:Phenylephrine; D015016:Yohimbine; D011343:Procaine; C024763:talipexole; C005298:benoxinate; D003000:Clonidine