Staubli U, Huston J P
Pharmacol Biochem Behav. 1979 May;10(5):783-6. doi: 10.1016/0091-3057(79)90333-2.
The effects of post-trial injection of substance P (SP) into the lateral hypothalamus (LH) and the ventromedial hypothalamus (VMH) on passive avoidance learning was studied in rats. In the VMH, 50 ng and 500 ng SP influenced neither learning of a step-down avoidance nor of an alcove avoidance response. In contrast to these findings, 500 ng SP injected into the LH significantly enhanced retention of the alcove avoidance task. Similarly, in the step-down avoidance experiment, learning was strongly facilitated by posttrial injection of 50 ng as well as 500 ng SP into the LH. These results, together with our previous data showing amnesia with posttrial injection of SP into amygdala and substantia nigra, suggest that exogenously applied SP influences the activity of those brain regions shown to contain high densities of SP-positive nerve terminals. Interestingly, the effects of posttrial SP injection parallel the effects of post-trial electrical brain stimulation on passive avoidance learning. Hence, posttrial SP retroactively facilitates or impairs learning depending on where in the brain it is injected.
研究了在大鼠中试验后向外侧下丘脑（LH）和腹内侧下丘脑（VMH）注射P物质（SP）对被动回避学习的影响。在VMH中，50 ng和500 ng的SP对逐步回避学习和壁龛回避反应的学习均无影响。与这些发现相反，向LH注射500 ng的SP显著增强了壁龛回避任务的记忆保持。同样，在逐步回避实验中，试验后向LH注射50 ng以及500 ng的SP强烈促进了学习。这些结果，连同我们之前的数据表明试验后向杏仁核和黑质注射SP会导致失忆，提示外源性应用的SP会影响那些显示含有高密度SP阳性神经末梢的脑区的活性。有趣的是，试验后注射SP的效果与试验后脑电刺激对被动回避学习的效果相似。因此，试验后注射SP根据其在脑中的注射部位，会追溯性地促进或损害学习。
