The olfactory function and imprinting of odorant information of the native stream play a critical role during the homing migration in fish. Pesticides may impair olfactory imprinting by altering olfaction and hormone functions. The present study aimed to determine how diazinon impacts olfactory epithelium morphology and cell composition, as well as hormone concentrations in Persian sturgeon (Acipenser persicus) during their lifetime in freshwater and, also during diazinon-free saltwater acclimation. Fingerlings were exposed to 0, 150, 300, and 450 μg·L⁻¹ of diazinon in freshwater for 7 days and then were transferred to diazinon-free saltwater by gradually increasing salinity up to 12 ppt. After diazinon exposure, the number of olfactory receptor cells (ORCs) and goblet cells (GCs) decreased and increased, respectively, and the expression of G-protein αolf (GPαolf) and calmodulin-dependent kinase II delta (CAMKIId) was down-regulated and up-regulated, respectively. Transferring the fish to diazinon-free saltwater (8 and 12 ppt) raised the number of ORCs, supporting cells (SCs), GCs, and GPαolf expression, and down-regulated CAMKIId without any significant differences among treatments. Exposure to diazinon increased whole-body cortisol at the high concentration, while decreased whole-body thyroxin (T4) and triiodothyronine (T3) in a dose-dependent manner. Although whole-body T4 and T3 increased in all the treatments after saltwater acclimation (8 and 12 ppt), the level of these hormones was lower in fish that had been exposed to diazinon than in the control. These results showed that diazinon can disrupt olfactory epithelium morphology and cell composition as well as hormone concentrations, which in turn may affect the olfactory imprinting in Persian sturgeon fingerlings.

在鱼类的归巢迁移过程中，天然流的嗅觉功能和气味信息的印记起着至关重要的作用。农药可能会通过改变嗅觉和激素功能来削弱嗅觉烙印。本研究旨在确定二嗪农如何影响嗅st上皮的形态和细胞组成，以及波斯st鱼（Acipenser persicus）在淡水生命中以及无二嗪农的海水驯化过程中的激素浓度。鱼种暴露于0、150、300和450μg·L ^-1淡水中的二嗪农达7天，然后通过逐渐增加盐度至12 ppt转移到不含二嗪农的盐水中。暴露于二嗪农后，嗅觉受体细胞（ORC）和杯状细胞（GCs）的数量分别减少和增加，并且G蛋白αolf（GPαolf）和钙调蛋白依赖性激酶IIδ（CAMKIId）的表达下调。和上调。将鱼转移到不含二嗪农的盐水中（8和12 ppt）可以提高ORC，支持细胞（SC），GC和GPαolf表达的数量，并下调CAMKIId的水平，而各处理之间无明显差异。在高浓度下，暴露于二嗪农会增加全身皮质醇，而剂量依赖性会降低全身甲状腺素（T4）和三碘甲状腺素（T3）。尽管盐水适应后（8和12 ppt）在所有处理中全身T4和T3均增加，但暴露于二嗪农的鱼体内这些激素的水平低于对照组。这些结果表明，二嗪农可以破坏嗅上皮的形态，细胞组成以及激素浓度，进而可能影响波斯st鱼鱼种的嗅觉印记。