Acute Effects of Anticholinesterase Agents on Pupillary Function.
Abstract
The analysis of acetylcholine (ACh) levels, metabolism and release, as well as the uptake of choline, were performed on segments of rat iris to investigate the mechanisms involved in the response of the iris to acute and chronic cholinesterase inhibition. At various times after the topical administration of 0.1 % DFP in sesame oil to the corneal surface, the rats were decapitated and the irises were removed. Pupil size was measured and ACh levels and cholinesterase activity were determined in each iris following extraction of remaining free DFP with chloroform. No changes were detected 1 min. after the DFP, but by 5 min., pupil diameter was reduced by 50%, esterase activity was reduced by 90%, and ACh was increased by 60%. There were no further changes 30 min. after the DFP, but by 60 min., ACh had returned to control levels even though esterase activity was still inhibited by 90% and pupil diameter was still reduced by over 50%. Based on these results, a mechanism of action of DFP involving multiple effects on ACh metabolism is proposed.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1982
- Accession Number
- ADA119239
Entities
People
- E. Giacobini
Organizations
- University of Connecticut