An ultrastructural and histochemical study of the short-term effects of 6-hydroxydopamine on adrenergic nerves in the domestic fowl.
1. The effects of 6-hydroxydopamine (6-OHDA) on adrenergic nerves in the domestic fowl have been investigated with ultrastructural and fluorescence histochemical methods.2. 6-OHDA depletes the nerves of catecholamine, initially by displacing it from the storage vesicles. 6-OHDA enters large as well as small vesicles, indicating that large granular vesicles in adrenergic nerves are sites of amine storage.3. Doses of 6-OHDA, insufficient to cause degeneration, still cause loading of the vesicles.4. The effects of various drugs on the action of 6-OHDA indicate that this drug must be taken up by the nerves and reach a critical extragranular axoplasmic concentration before degeneration will occur; 6-OHDA bound in the vesicles plays no part in the degenerative process.
D000661:Amphetamine / Q000494:pharmacology; D000818:Animals; D002395:Catecholamines / Q000032:analysis; D002645:Chickens; D003891:Desipramine / Q000494:pharmacology; D004298:Dopamine / Q000494:pharmacology*; D006651:Histocytochemistry; D008680:Metaraminol / Q000494:pharmacology; D008854:Microscopy, Electron; D008856:Microscopy, Fluorescence; D009474:Neurons / Q000166:cytology; D012110:Reserpine / Q000494:pharmacology; D013564:Sympathetic Nervous System / Q000187:drug effects*
D002395:Catecholamines; D008680:Metaraminol; D012110:Reserpine; D000661:Amphetamine; D003891:Desipramine; D004298:Dopamine