Depressive disorder ranks as a major bur-den of disease worldwide,yet the current antidepressant medications are limited by frequent non-responsiveness and significant side effects.The lateral septum(LS)is thought to control of depression,however,the cellular and circuit substrates are largely unknown.Here,we identified a subpopulation of LS GABAergic adenosine A2A receptors(A2AR)-positive neurons mediating depres-sive symptoms via direct projects to the lateral habenula(LHb)and the dorsomedial hypothalamus(DMH).Activa-tion of A2AR in the LS augmented the spiking frequency of A2AR-positive neurons leading to a decreased activation of surrounding neurons and the bi-directional manipula-tion of LS-A2AR activity demonstrated that LS-A2ARs are necessary and sufficient to trigger depressive pheno-types.Thus,the optogenetic modulation(stimulation or inhibition)of LS-A2AR-positive neuronal activity or LS-A2AR-positive neurons projection terminals to the LHb or DMH,phenocopied depressive behaviors.Moreover,A2AR are upregulated in the LS in two male mouse mod-els of repeated stress-induced depression.This identifica-tion that aberrantly increased A2AR signaling in the LS is a critical upstream regulator of repeated stress-induced depressive-like behaviors provides a neurophysiological and circuit-based justification of the antidepressant poten-tial of A2AR antagonists,prompting their clinical transla-tion.

Objective: To explore the mechanical changes and distributions of pressure in each characteristic intervertebral disc after short segment unilateral pedicle screw fixation in Chinese mini-pigs. Methods: Six characteristic spine segments of 6-week-old Chinese mini-pigs (T3-4、T11-12、T15-L1、L3-4、L4-5 segments with adjacent upper and lower vertebrae) were chosen as experimental models. A biomechanical machine and pressure sensitive film were used to measure the pressure on the vertebral columns when they were subjected to pressures of 200 N as unfixed group. Compression was carried out under vertical, 5 °flexion, 5 °extension and 5 °lateral bending, respectively. Then the PCF (posterior cervical fixation) system were fixed on all segments (left side) as fixed group, and biomechanical tests were repeated to obtain data. A Fujitsu densitometer (Japan) was used to measure the pressure on each direction of the pressure sensitive film. Results: In vertical pressures, 5° flexion and 5°extension conditions, the posterior pressure of T3-4、T11-12、T15-L1、L3-4 and L4-5 intervertebral discs were decreased after fixation, the differences were statistically significant; The fixed side pressures of T3-4、T11-12、T15-L1、L3-4 and L4-5 in the fixed group were significantly lower than those in the unfixed group in the corresponding segments and load conditions, and the differences were statistically significant. The concave disc pressures of T3-4、T11-12、T15-L1、L3-4 and L4-5 in the fixed group were 0.83±0.12, 0.93±0.12, 0.50±0.05, 0.60±0.10 and 0.55±0.08 MPa respectively, which were lower than those of the unfixed group 1.70±0.18, 1.79±0.14, 1.84±0.22, 1.74±0.28, 1.60±0.23 MPa, and the differences were statistically significant. The total disc pressure of the fixed group was significantly lower than that of the non-fixed group in vertical compression, 5 degree flexion and 5 degree extension, and the differences were statistically significant. Conclusion Unilateral pedicle screw fixation can decrease the pressure on fixed side of fixed group in all conditions and change the distribution of pressure. The posterior pressure decreased particularly. Short- segment unilateral pedicle screw fixation can decrease the average pressure of intervertebral disc, which is an excellent surgery in curing scoliosis in young children.