Effect And Mechanism Of Chronic Intermittent Hypoxia On Depression Disorder In Rats

OBJECTIVE:obstructive sleep apnea hypopnea syndrome(OSAHS)is a clinically common sleep respiratory disease(SDB).it is a clinical syndrome that results in recurrent complete or partial obstruction of the upper airway during night sleep,resulting in apnea and/or hypopnea.chronic intermittent hypoxia(CIH)is the main pathophysiological manifestation that can cause systemic multiple organ dysfunction.Depression disorder is the most common neuropsychological symptom in OSAHS patients.This experiment established a CIH animal model with OSAHS pathophysiological characteristics to study the effect of CIH on depression status in rats and analyzed its possible mechanism in order to provide ideas for clinical treatment.METHODS:24 healthy male SD rats were randomly divided into control group(CON),CIH group and removal of hypoxia group(RH),8 in each group.No special treatment for rats in CON group,rats in CIH group suffered 8 hours intermittent hypoxia everyday,the duration of experiment was 8 weeks,and those in RH group was treated as same as those in CIHgroup in the first 4 weeks and were raised normally in the next 4 weeks.At the end of the model,the brain metabolism was observed by PET / CT imaging,and the depression like emotional state was evaluated by sucrase preference test(SPT),open field test and forced swimming test(FST);After the behavioral experiment,the rats were killed,the brain tissues were taken,the synaptic morphology and number of hippocampal CA1 area were observed under the electron microscope,and the contents of PSD-95,NR2 B,BDNF,5-HT,Da,NE in hippocampal area were measured by enzyme-linked immunosorbent assay(ELISA).RESULT:1.Compared to CON group,the SUV value of CIH group increased,but there was no significant difference(P > 0.05);2.There was no significant difference in sugar water preference rate(P > 0.05);3.Compared to CON group,the central activity path ratio of CIH and RH groups in the center of open field test was reduced(P < 0.05);4.Compared to CON group,the immobility time of forced swimming was prolonged in CIH group(P < 0.05);5.Under transmission electron microscope,compared to CON group,the number of synapses was reduced in CIH group(P < 0.05);6.The hippocampal levels of 5-HT,NE,BDNF and PSD-95 were decreased in CIH group compared to those in CON group(P < 0.05,P <0.01).For RH group,the levels of 5-HT and BDNF in hippocampus were decreased compared to CON group(P < 0.05).When compared to CIH group,the hippocampal content of 5-HT content was markedly increased in RH group(P < 0.05).CONCLUSION : CIH mightly increase the risk of depression,mechanisms may be associated with decreased expression levels of 5-HT?BDNF in the hippocampus and altered synaptic plasticity.Correcting hypoxia can partially improve nerve injury.