ABNORMAL FORMATION OF SEROTONERGIC NETWORK AND STRESS ACTION.

在4周龄时，母鼠的声音应激(800赫兹，每隔一分钟77分贝，持续15分钟/天，从妊娠第10天到18天)与强迫游泳应激(15分钟/天)相结合，可导致雄性后代运动活动丧失的增强，称为情绪行为，但雌性后代没有。在6周龄时，母体压力还导致雄性后代在水迷宫测试中的错误总数增加，但雌性后代没有增加。用丁螺环酮处理后(应激前30min，妊娠第8~18天)，这些应激对情绪行为和学习行为的影响被消除。因此，孕期应激对新生大鼠的情绪行为和学习能力可能具有性别依赖性影响。在神经化学方面，母体声应激和强迫游泳应激以性别依赖的方式影响5-羟色胺受体和5-羟色胺转运体与其特定配体的结合活性。对发育脑5-羟色胺受体的结合活性无明显影响。因此，推测母体应激可能导致5-羟色胺能网络的异常形成，并可能损害新生大鼠的情绪行为和学习能力。

Maternal sound stress (800 Hz ; 77dB, every other minute for 15 min/day, from day 10 to 18 of gestation), combined with forced swimming stress (15 min/day), was found to cause potentiation of sound-induced loss of locomotor activity, referred to as emotional behavior, of male offspring, but not that of female offspring, at 4 weeks of age. Maternal stress also caused an increase in the total number of errors by male, but not female offspring in the water-maze test at 6 weeks of age. These effects of stress on emotional behavior and learning behavior were abolished when dams were pretreated with buspirone (30 min before the stress, from day 8 to 18 of gestation). Thus, prenatal stress might have sex-dependent effects on emotional behavior and learning ability of neonatal rats. As to the neurochemical aspects, maternal sound stress, combined with forced swimming stress, was found to influence the binding activity of 5-HT_<2A> receptor and 5-HT transporter to their specific ligand in sex-dependent manner. No effect was observed in the binding activity of 5-HT_<1A> receptor of developing brain. Thus, it was speculated that maternal stress might cause abnormal formation of serotonergic network, and might impair the emotional behavior and learning ability of neonatal rats.