Neuropathological Changes And Treatment In Goldfish After Traumatic Injuries To Balance And Movement

Goldfish(Carassius auratus) are extensively used as neurophysiological structure/function model organisms.However,the relationship among traumatic stresses and behaviour,activation of specific neuropathological pocesses in certain brain regions in fish still remains elusive and has been rarely explored.In the present study,the exploration of traumatic injuries induced neuropathological changes in regards to balance and movement was performed.Quantitative description of behavioural changes was provided and an increase of 5-HT_2a receptor in the cerebellum of goldfish after traumatic injuries was observed,supporting the associations between serotonergic system and behavior control.Meanwhile,an apparent apoptosis phenomenon as well as an increase of caspase-8 was found among goldfish with fin ablation compared to controls,which was very interesting and might shed new light on the development of self-modulation.In addition,up-regulation of c-fos expression was significant in brain of goldfish with lesions.The activation of apoptosis suggested the possibility of self-protection through the pathway of cell death. Taken together,these results demonstrated that fin ablation did induce obvious behavioural and neuropathological changes,indicating that goldfish could represent a powerful system to study the underlying basis of the post-stress response to traumatic injuries and it was also feasible to develop into the model of PTSD. With respect to the treatment of neuropathological changes and behavioral disorder induced by traumatic injuries,we selected two CNS drugs(doxepin and selective serotonin reuptake inhibitors(SSRI)) to investigate neuroprotective effects,as they are characterized by high clinical effectiveness and good tolerability.The evaluation the expression of 5-HT_2a receptor,5-HT_2c receptor,c-fos,BAD protein was carried out. The down-regulation of 5-HT_2a receptor and up-regulation of 5-HT_2c receptor were observed following treatment compared with injured group,and decreased expression of BAD protein but no effect on c—fos protein levels were also found,indicating that traumatic injuries-induced behavioral and neuropathological changes could be partly normalized by the treatment of CNS drugs,through the coordination of the serotonergic(5-HT) receptor level and apoptotic process.However,the traumatic injury model for further analyses of doxepin and SSRI effects are needed,especially at the behavioral level.