Despite well-documented neurotoxic and ototoxic properties, styrene remains commonly used in industry. Its effects on the cochlea have been extensively studied in animals, and epidemiological and animal evidence indicates an impact on balance. However, its influence on the peripheral vestibular receptor has yet to be investigated. Here, we assessed the vestibulotoxicity of styrene using an in vitro model, consisting of three-dimensional cultured newborn rat utricles filled with a high‑potassium (K⁺) endolymph-like fluid, called “cysts”. K⁺ entry in the cyst (“influx”) and its exit (“efflux”) are controlled by secretory cells and hair cells, respectively. The vestibular epithelium's functionality is thus linked to K⁺ concentration, measured using a microelectrode.

Known inhibitors of K⁺ efflux and influx validated the model. Cysts were subsequently exposed to styrene (0.25; 0.5; 0.75 and 1 mM) for 2 h or 72 h. The decrease in K⁺ concentration measured after both exposure durations was dose-dependent, and significant from 0.75 mM styrene. Vacuoles were visible in the cytoplasm of epithelial cells from 0.5 mM after 2 h and from 0.25 mM after 72 h.

The results presented here are the first evidence that styrene may deregulate K⁺ homeostasis in the endolymphatic space, thereby altering the functionality of the vestibular receptor.

尽管有充分记录的神经毒性和耳毒性，但苯乙烯仍是工业上常用的物质。在动物中已广泛研究了其对耳蜗的作用，流行病学和动物证据表明对平衡的影响。但是，其对周围前庭受体的影响尚待研究。在这里，我们使用体外模型评估了苯乙烯的前庭毒性，该模型由三维培养的新生大鼠尿囊组成，其中充满了高钾（K ⁺）内淋巴样液体，称为“囊肿”。囊肿中的K ⁺入口（“流入”）和其出口（“流出”）分别由分泌细胞和毛细胞控制。因此，前庭上皮的功能与K ⁺ 浓度，使用微电极测量。

已知的K ⁺外排和流入抑制剂可验证该模型。随后将囊肿暴露于苯乙烯（0.25; 0.5; 0.75和1 mM）2 h或72 h。两次暴露持续时间后测得的K ⁺浓度降低均与剂量有关，从0.75 mM苯乙烯开始显着。2小时后从0.5 mM开始，72小时后从0.25 mM开始，在上皮细胞的细胞质中可见液泡。

此处给出的结果是苯乙烯可能会破坏内淋巴间隙中K ⁺稳态的首个证据，从而改变前庭受体的功能。