Alterations in Autonomic Function in the Guinea Pig Eye Following Exposure to Dichlorvos Vapor
Published on Oct 1, 2008in Journal of Ocular Pharmacology and Therapeutics1.79
· DOI :10.1089/jop.2008.0020
The present study investigated the effect of the organophosphate, dichlorvos (DDVP), on ocular function and cholinesterase activity in guinea pigs, using a single-animal-head-only vapor exposure system. All animals exhibited signs of mild organophosphate poisoning (e.g., salivation, chewing, lacrimation, urination, defecation, and rhinorhea) after the 20-min exposure, regardless of the DDVP exposure concentration (e.g., 35 mg/m3, 55 mg/m3, and 75 mg/m3). Pupil constriction or miosis was the most pronounced effect seen after vapor exposure. The postexposure pupil size for the 35 mg/m3 group was 45.8 ± 3.68% of the preexposure baseline measurement. Postexposure pupil size in the 55- (38 ± 1.36%) and 75 mg/m3 (38.1 ± 1.72%) groups was significantly less than both the preexposure baseline level and the 35 mg/m3 group. All groups exhibited enhanced an pupillary response to light after DDVP exposure. The enhanced light response remained even after recovery from miosis (∼1 h after exposure). Measurement of choli...