Organophosphate-related ototoxicity: Description of the vestibulocochlear system ultrastructural aspects of guinea pigs.
Organophosphate toxic agents are used in agriculture and are currently part of the group of toxic agents which can lead to hearing loss, in which we have solvents, metals and asphyxiation agents.


OBJECTIVE
To analyze the acute ototoxic action of a group of organophosphate agents in the vestibulo-cochlear system. This is a prospective experimental study.


METHODS
We used male albino guinea pigs, broken down into three groups, to which we provided distilled water (group 1 - control), agrotoxic agent - 0.3 mg/Kg/day (group 2), agrotoxic - 3 mg/Kg/day (group 3), during 7 seven consecutive days. The most used agrotoxic agent was Tamaron BR (metamidophos). The anatomical evaluation of the cochlea, saccule and utricle was carried out by means of electronic scanning microscopy after the use of the agrotoxic agent.


RESULTS
The guinea pigs submitted to the organophosphate presented cochlear morphological alterations with lesions on the three turns analyzed, as well as cilia alterations in the saccule and utricle, intensified according to the agent dosage.


CONCLUSIONS
The morphological alterations seen in the hair cells exposed to daily doses of organophosphate promote evidences of an acute deleterious effect of agrotoxic agents on the vestibulo-cochlear system.
Körbes
Daiane
D
Human Communication Disorders graduate program, Santa Maria Federal University, Santa Maria, RS, Brazil.
Silveira
Aron Ferreira da
AF
Hyppolito
Miguel Angelo
MA
Munaro
Gisiane
G
D000818:Animals; D003051:Cochlea / Q000187:drug effects* / Q000648:ultrastructure; D004305:Dose-Response Relationship, Drug; D006168:Guinea Pigs; D007306:Insecticides / Q000633:toxicity*; D008297:Male; D008855:Microscopy, Electron, Scanning; D009946:Organothiophosphorus Compounds / Q000633:toxicity*; D011446:Prospective Studies; D014722:Vestibule, Labyrinth / Q000187:drug effects* / Q000648:ultrastructure
D007306:Insecticides; D009946:Organothiophosphorus Compounds; C014655:methamidophos