Adolescent toluene exposure produces enduring social and cognitive deficits in mice: An animal model of solvent-induced psychosis

Abstract

OBJECTIVES: Abuse of toluene-containing volatile solvents by adolescents is a significant public health problem. The present study characterized the long-term behavioural and neurochemical consequences of toluene exposure during adolescence. METHODS: Male NMRI mice received one injection per day of either toluene (600 mg/kg) or corn oil during postnatal days (PN) 35-37 and (750 mg/kg) during PN38-39 and PN42-46. A variety of psychiatric disorder-relevant behavioural tests were examined at PN56-P84. RESULTS: The toluene-exposed mice were significantly deficient in the social interaction test, nesting behaviour, social dominance tube test, and novel objective recognition test. However, toluene exposure did not affect locomotor activity and behavioural profiles in the forced swimming test, tail suspension test, emergence test and elevated plus maze. Neurochemically, the turnover rates of dopamine in the prefrontal cortex, striatum and nucleus accumbens were reduced in toluene-treated mice. CONCLUSIONS: Adolescent toluene exposure leads to social deficits and cognitive impairment at adulthood as well as neurochemical dysfunction in mice, which correlate with the symptoms observed in patients suffering from solvent-induced psychosis. These findings highlight the need for understanding the effects of solvent abuse on the developing nervous system and reveal an animal model suitable for research into pathophysiology of neurological and psychiatric consequences of solvent abuse.