Abstract
1. The technique of intraocular administration of drugs is described.
2. Ergotamine tartrate instilled into the conjunctival sac, or injected intraocularly, produces maximal constriction of the pupil.
3. This miosis is due to sympathetic paralysis, for faradic stimulation of the cephalic end of the cut cervical sympathetic nerve or the intravenous injection of ephinephrine does not cause dilatation of the pupil previously constricted by ergotamine.
4. The extreme miosis following ergotamine injection is made possible by sympathetic paralysis which allows the parasympathetic impulses to exert their full action.
5. Ergotamine produces dilatation of the pupil—not constriction—due to sympathetic stimulation in the guinea pig.
6. The fact that ergotamine produces paralysis of the sympathetic end organs in the dilator muscle of the cat's iris is utilized to study the action of cocaine and ephedrine, whose sympathomimetic nature has been questioned. The results indicate that these drugs have indeed sympathetic affinities.
Footnotes
- Received November 8, 1929.
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