School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, SP 14800-903, Brazil.
Joint UFSCar-UNESP Graduate Program in Physiological Sciences, São Carlos, SP 13565-905, Brazil.
Cells. 2021 May 17;10(5):1217. doi: 10.3390/cells10051217.
We investigated the role of angiotensin II type 1 (AT receptor) and type 2 (AT receptor) and MAS receptors present in the medial amygdaloid nucleus (MeA) in behavioral changes in the forced swimming test (FST) evoked by acute restraint stress in male rats. For this, rats received bilateral microinjection of either the selective AT receptor antagonist losartan, the selective AT receptor antagonist PD123319, the selective MAS receptor antagonist A-779, or vehicle 10 min before a 60 min restraint session. Then, behavior in the FST was evaluated immediately after the restraint (15 min session) and 24 h later (5 min session). The behavior in the FST of a non-stressed group was also evaluated. We observed that acute restraint stress decreased immobility during both sessions of the FST in animals treated with vehicle in the MeA. The decreased immobility during the first session was inhibited by intra-MeA administration of PD123319, whereas the effect during the second session was not identified in animals treated with A-779 into the MeA. Microinjection of PD123319 into the MeA also affected the pattern of active behaviors (i.e., swimming and climbing) during the second session of the FST. Taken together, these results indicate an involvement of angiotensinergic neurotransmissions within the MeA in behavioral changes in the FST evoked by stress.
我们研究了血管紧张素 II 型 1（AT 受体）和 2 型（AT 受体）以及存在于内侧杏仁核（MeA）中的 MAS 受体在急性束缚应激引起的雄性大鼠强迫游泳试验（FST）中的行为变化中的作用。为此，大鼠在 60 分钟束缚期前 10 分钟接受双侧微注射选择性 AT 受体拮抗剂洛沙坦、选择性 AT 受体拮抗剂 PD123319、选择性 MAS 受体拮抗剂 A-779 或载体。然后，在束缚后立即（15 分钟疗程）和 24 小时后（5 分钟疗程）评估 FST 中的行为。还评估了非应激组在 FST 中的行为。我们观察到，急性束缚应激降低了在 MeA 中接受载体处理的动物在 FST 的两个疗程中的不动性。在第一疗程中，MeA 内给予 PD123319 可抑制不动性，而在 MeA 内给予 A-779 的动物则未发现第二疗程中的作用。PD123319 微注射到 MeA 也影响了 FST 的第二个疗程中的主动行为（即游泳和攀爬）模式。总之，这些结果表明，血管紧张素能神经传递在应激引起的 FST 中的行为变化中涉及 MeA 内的作用。
