シスプラチン誘発味覚障害モデルラットにおける味覚神経変性

抄録

Cancer chemotherapy often induces taste disturbance that reduces quality of life of the cancer patients. However, the mechanisms underlying chemotherapy-induced taste disturbance are poorly understood. It is known that anti-cancer agents that cause taste disturbance, such as platinum agents, also induces peripheral neuropathy that based on neurotoxicity. In this study, we investigated the alteration of the gustatory nerve and taste receptors in the cisplatin-induced taste disturbance model rats. We made taste disturbance model by repeated administrations of cisplatin (2 mg/kg, i.p.) once a week for 8 weeks. The taste sensitivity to brief-access test was significantly decreased in cisplatin-administered rats on 5 and 8 weeks, compared to control group. Consistently, in electron microscopic analysis, the axonal degeneration in the gustatory nerve was observed on 5 and 8 weeks. However, the expression levelof sweet taste receptor T1R2mRNA in the taste bud was decreased only on 8 weeks, and that of bitter taste receptor T2R107 mRNAwas not changed. These data show that alteration of taste sensitivity was correlated with axonal degeneration in gustatory nerve, rather than that of taste receptor level. These results suggest that the taste disturbanceinduced by cisplatinis related to the gustatory nerve degeneration.