Department of Physiology and Pharmacology, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Laboratory of Animal Reproduction, Universidade Federal de Santa Maria, Santa Maria, RS, Brazil.
Microb Pathog. 2019 Jul;132:261-265. doi: 10.1016/j.micpath.2019.05.017. Epub 2019 May 10.
Aeromonosis is a fish disease that leads to haemorrhagic septicaemia and high mortality. The detection of early behavioural changes associated to this disease could be helpful in anticipating the initiation of treatment, increasing the probability of success. The influence of this disease on the hypothalamic-pituitary-interrenal (HPI) axis and on the brain expression of heat shock proteins (HSP) is little known. Therefore, the aim of this study was to evaluate the effect of Aeromonas hydrophila infection on individual behaviour and brain expression of genes related to stress (slc6a2, hsp90, hspa12a, hsd20b, hsd11b2, crh) in silver catfish (Rhamdia quelen). Thirty fish were divided into healthy and infected groups. The fish of the infected group were inoculated intramuscularly with 50 μL of bacterial suspension (6.4 × 10 CFU/mL), while control animals received 50 μL of saline. On day five post-infection, animals were submitted to the novel tank test, euthanized, and the brain was collected for molecular analysis. Infected fish swam more in the unknown aquarium and presented an increase in brain expression of genes related to HSP (hspa12a) and the route of cortisol synthesis (crh) when compared to uninfected fish. Therefore, this disease causes hyperlocomotion related to stress.
气单胞菌病是一种鱼类疾病，可导致出血性败血症和高死亡率。检测与这种疾病相关的早期行为变化可能有助于提前开始治疗，增加成功的可能性。这种疾病对下丘脑-垂体-肾上腺（HPI）轴和大脑中热休克蛋白（HSP）表达的影响知之甚少。因此，本研究旨在评估嗜水气单胞菌感染对银鲶（Rhamdia quelen）个体行为和与应激相关的基因（slc6a2、hsp90、hspa12a、hsd20b、hsd11b2、crh）在大脑中的表达的影响。将 30 条鱼分为健康组和感染组。感染组的鱼通过肌肉内注射 50µL 细菌悬浮液（6.4×10 CFU/mL）进行接种，而对照组动物则接受 50µL 生理盐水。感染后第五天，动物进行了新鱼缸测试，然后处死并采集大脑进行分子分析。与未感染的鱼相比，感染鱼在未知水族馆中游泳更多，并且大脑中与 HSP（hspa12a）和皮质醇合成途径（crh）相关的基因表达增加。因此，这种疾病会导致与应激相关的过度运动。
