Lénárd L, Kertes Erika
Neurophysiology Research Group of the Hungarian Academy of Sciences at Institute of Physiology, Pécs University Medical School.
Acta Biol Hung. 2002;53(1-2):95-104. doi: 10.1556/ABiol.53.2002.1-2.11.
Neuropeptide substance P (SP) has reinforcing and memory facilitating effects after its peripheral or central application. Rats self-inject SP into the ventromedial caudate-putamen and SP microinjections into the basal forebrain induce place preference with a simultaneous increase of dopamine level. In the amygdaloid body SP positive neurones and terminals have been identified. The aim of the present study was to examine the possible reinforcing effects of SP in the basolateral amygdala (ABL). CFY male rats were conditioned in two-compartment passive avoidance paradigm and place preference was examined in two-compartment-box and in circular open field. Animals were microinjected bilaterally with 10 ng SP, 100 ng SP or vehicle solution (0.4 microl/side) into the ABL. Results showed that post-shock infusion of 10 ng SP significantly enhanced passive avoidance learning while 100 ng SP was ineffective. In two-compartment-box and in circular open field place preference did not develop after SP treatments, however. Our data are the first to demonstrate that SP in the ABL is involved in learning and memory processes related to aversive situations. Results that SP microinjections were not followed by rewarding-reinforcing consequences in place preference paradigms indicate that the local SP network in the ABL is not involved in neuronal circuitry responsible for addictive behaviour.
神经肽P物质（SP）在其外周或中枢应用后具有强化和促进记忆的作用。大鼠会自我向腹内侧尾状核-壳核注射SP，并且向基底前脑微量注射SP会诱导位置偏爱，同时多巴胺水平升高。在杏仁核中已鉴定出SP阳性神经元和终末。本研究的目的是检测SP在基底外侧杏仁核（ABL）中可能的强化作用。将CFY雄性大鼠置于两室被动回避范式中进行训练，并在两室箱和圆形旷场中检测位置偏爱。动物双侧向ABL微量注射10 ng SP、100 ng SP或溶剂溶液（0.4微升/侧）。结果显示，休克后注射10 ng SP显著增强了被动回避学习，而100 ng SP则无效。然而，在两室箱和圆形旷场中，SP处理后并未形成位置偏爱。我们的数据首次证明ABL中的SP参与了与厌恶情境相关的学习和记忆过程。在位置偏爱范式中，SP微量注射后未出现奖赏强化结果，这表明ABL中的局部SP网络不参与负责成瘾行为的神经回路。
