Inhaled toluene can modulate the effects of anesthetics on the middle-ear acoustic reflex

Isoflurane anesthesia suppresses distortion product otoacoustic emissions in rats

“…The middle ear reflex (MER) is activated bilaterally in response to intense sound, which leads to the constriction of the stapedius muscle, and subsequent tensioning of the ossicular chain (Møller, 1974). Both isoflurane and k/x can suppress the MER (Campo et al., 2013; Chambers et al., 2012). However, the rat MER is not activated until approximately 75 dB after a presentation duration of 10–20 ms (Pilz et al., 1997), and therefore is unlikely to have a significant impact on the majority of DP amplitudes in the present study.…”

Chemical exposure and hearing loss

“…66 Many abused inhalants such as toluene may enhance inhibitory synaptic responses through their action on specific sites or through similar mechanisms of action to other CNS depressants, like anesthetics. 67,68 For instance, N-methyl-D-aspartic acid, 69 δ-aminobutyric acid, glycine, 70 adenosyl triphosphate, 71 serotonin, 72 and nicotinic acetylcholine receptors 73 are all involved in CNS function and are sensitive to toluene. Recently, Lataye et al 74 and Maguin et al 75 showed that toluene could alter acetylcholine receptors and voltage-dependent Ca 2+ channels function in in vivo studies.…”

Effects of thiocolchicoside, a commonly used myorelaxant, on the acoustic reflex

“…Acetylcholine and glutamate play an important role in the afferent and efferent systems of the auditory pathway. The same study also showed that isoflurane, another solvent used in general anaesthesia, has a similar effect to that of toluene 18 …”

“…Solvents used in the paint and adhesive industry are also suggested to increase the harmful effects of noise by suppressing the acoustic reflex 17 . The effects of toluene on the acoustic reflex were investigated in rats under anaesthesia 18 . According to that study, toluene suppressed the acoustic reflex in anaesthetised rats.…”