Padovan C M, Guimarães F S
Departamento de Farmacologia, Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Brasil.
Braz J Med Biol Res. 1993 Oct;26(10):1085-9.
To investigate the role of hippocampal 5-HT neurotransmission on adaptation to aversive events, individually housed male Wistar rats (200-250 g) were immobilized for 2 h and tested 24 h later in an elevated plus-maze. Immediately after the restraint period they received bilateral microinjections into the dorsal hippocampus of either saline (0.5 microliters) or the nonselective 5-HT1 antagonist dl-propranolol (20 nmol/0.5 microliters). In a second experiment the first microinjection of saline or dl-propranolol was followed by a second microinjection of saline (0.5 microliters) or the 5-HT reuptake blocker zimelidine (20 nmol/0.5 microliters). Although dl-propranolol alone did not change exploration of the elevated plus-maze, it antagonized the increase in the percentage of open arm entries induced by zimelidine (26.0 +/- 4.1 vs 5.64 +/- 3.7 in controls). These results are compatible with the view that post-synaptic 5-HT1a receptors in the hippocampus mediate adaptive or coping responses to aversive events.
为研究海马5-羟色胺神经传递在适应厌恶事件中的作用，将单独饲养的雄性Wistar大鼠（200 - 250克）固定2小时，并在24小时后于高架十字迷宫中进行测试。在约束期结束后，立即对其双侧海马背侧进行微量注射，注射物为生理盐水（0.5微升）或非选择性5-羟色胺1拮抗剂dl-普萘洛尔（20纳摩尔/0.5微升）。在第二个实验中，第一次微量注射生理盐水或dl-普萘洛尔后，接着进行第二次微量注射，注射物为生理盐水（0.5微升）或5-羟色胺再摄取阻滞剂齐美利定（20纳摩尔/0.5微升）。虽然单独使用dl-普萘洛尔不会改变在高架十字迷宫中的探索行为，但它拮抗了齐美利定诱导的开臂进入百分比的增加（对照组中分别为26.0±4.1和5.64±3.7）。这些结果与海马中突触后5-羟色胺1a受体介导对厌恶事件的适应性或应对反应这一观点相符。
