Neuroscience Research Center, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Student Research Committee, Baqiyatallah University of Medical Sciences, Tehran, Iran.
Amino Acids. 2024 Feb 10;56(1):13. doi: 10.1007/s00726-023-03380-4.
Behavioral and functional studies describe hemispheric asymmetry in anxiety and metabolic behaviors in responses to stress. However, no study has reported serotonergic receptor (the 5-HT receptor) lateralization in the basolateral amygdala (BLA) in vivo on anxiety and metabolic behaviors under stress. In the present study, the effect of unilateral and bilateral suppression of the 5-HT receptor in the BLA on anxiety, and metabolic responses to chronic restraint stress was assessed. Male Wistar rats 7 days after cannulation into the BLA received chronic restraint stress for 14 consecutive days. 20 minutes before induction of stress, WAY-100-635 (selective 5-HT antagonist) or sterile saline (vehicle) was administered either uni- or bi-laterally into the BLA. Behavioral (elevated plus maze; EPM, and open field test), and metabolic parameter studies were performed. Results showed that stress causes a significant increase in weight gain compared to control. In the non-stress condition, the left and bilaterally, and in the stress condition the right, left, and both sides, inhibition of 5-HT in the BLA reduced weight gain. In the restraint stress condition, only inhibition of the 5-HT receptor in the left BLA led to decreased food intake compared to the control group. In stress conditions, inhibition of the 5-HT receptor on the right, left, and bilateral BLA increased water intake compared to the stress group. Inhibition of the 5-HT receptor on the left side of the BLA by WAY-100-635 induced anxiety-like behaviors in stressed rats. Similarly, WAY-100-635 on the left BLA effectively caused anxiety-like behaviors in both EPM and open field tests in the control animals. In conclusion, it seems that 5-HT receptors in the left BLA are more responsible for anxiety-like behaviors and metabolic changes in responses to stress.
行为和功能研究描述了焦虑症的半球不对称性和代谢行为对压力的反应。然而，目前尚无研究报道活体条件下边缘下核（BLA）5-羟色胺受体（5-HT 受体）的偏侧化在应激条件下的焦虑症和代谢行为中的作用。在本研究中，评估了单侧和双侧抑制 BLA 中的 5-HT 受体对焦虑症以及代谢对慢性束缚应激的反应的影响。在 BLA 插管后 7 天的雄性 Wistar 大鼠接受了连续 14 天的慢性束缚应激。在诱导应激前 20 分钟，将 WAY-100-635（选择性 5-HT 拮抗剂）或无菌盐水（载体）单侧或双侧注入 BLA。进行了行为（高架十字迷宫；EPM 和旷场试验）和代谢参数研究。结果表明，与对照组相比，应激会导致体重明显增加。在非应激条件下，左侧和双侧，以及在应激条件下右侧、左侧和双侧抑制 BLA 中的 5-HT 可减少体重增加。在束缚应激条件下，只有抑制左侧 BLA 中的 5-HT 受体可导致与对照组相比的摄食量减少。在应激条件下，抑制右侧、左侧和双侧 BLA 的 5-HT 受体可增加与应激组相比的饮水量。WAY-100-635 抑制 BLA 的左侧 5-HT 受体可诱导应激大鼠出现焦虑样行为。同样，WAY-100-635 对 BLA 的左侧也可有效引起对照组动物在 EPM 和旷场测试中的焦虑样行为。总之，似乎 BLA 的左侧 5-HT 受体更负责对压力的焦虑样行为和代谢变化的反应。
