title: Denervation supersensitivity in Horner's Syndrome.
abstract: The mechanism of denervation supersensitivity was investigated, using the pupillary system as an experimental model. A pharmacological study was carried out in six patients with Horner's syndrome due to postganglionic lesions. Administration of cocaine 4 percent resulted in dilatation of the normal pupil, while subsequent instillation of phenylephrine (2.5-5 percent) produced equal dilatation in both eyes. The results of the study indicate that denervation supersensitivity of the pupil can be explained solely by impaired reabsorption of catecholamines.
mesh_terms: D000328:Adult; D003042:Cocaine / Q000494:pharmacology; D003714:Denervation; D004106:Dilatation; D005260:Female; D006732:Horner Syndrome / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D010656:Phenylephrine / Q000494:pharmacology; D011680:Pupil / Q000187:drug effects; D014276:Trigeminal Nerve / Q000503:physiopathology; D014277:Trigeminal Neuralgia / Q000503:physiopathology*
chemical_list: D010656:Phenylephrine; D003042:Cocaine