Brennan P A, Kishimoto J
AFRC Institute of Animal Physiology and Genetics Research, Babraham, Cambridge, UK.
Brain Res. 1993 Aug 13;619(1-2):306-12. doi: 10.1016/0006-8993(93)91625-3.
The putative intercellular transmitter nitric oxide has been suggested to play a role in synaptic plasticity in several models of learning and memory. We have investigated the cellular localisation of nitric oxide synthase in the accessory olfactory bulb of the mouse, using immunohistochemistry and NADPH diaphorase histochemistry. The strikingly high levels of nitric oxide synthase observed in the accessory olfactory bulb were found to be due almost exclusively to its localisation in granule cell interneurons. In mice the accessory olfactory bulb has been proposed as the site of synaptic changes occurring during the formation of an olfactory memory to male pheromones. In an attempt to disrupt the formation of this olfactory memory, we used local infusions of the nitric oxide synthase inhibitor L-NG-nitroarginine, into the olfactory bulb over the critical period for memory formation. Infusions of L-NG-nitroarginine at doses that effectively inhibited nitric oxide synthase activity did not prevent memory formation. The apparent resistance of this memory to inhibition of nitric oxide synthase activity may reflect the special nature of the mitral cell to granule cell reciprocal synapse in the accessory olfactory bulb.
据推测，细胞间递质一氧化氮在多种学习和记忆模型的突触可塑性中发挥作用。我们利用免疫组织化学和NADPH黄递酶组织化学方法，研究了小鼠副嗅球中一氧化氮合酶的细胞定位。在副嗅球中观察到的一氧化氮合酶的显著高水平几乎完全归因于其在颗粒细胞中间神经元中的定位。在小鼠中，副嗅球被认为是在形成对雄性信息素的嗅觉记忆过程中发生突触变化的部位。为了试图破坏这种嗅觉记忆的形成，我们在记忆形成的关键时期，将一氧化氮合酶抑制剂L-NG-硝基精氨酸局部注入嗅球。以有效抑制一氧化氮合酶活性的剂量注入L-NG-硝基精氨酸并不能阻止记忆形成。这种记忆对一氧化氮合酶活性抑制的明显抗性可能反映了副嗅球中二尖瓣细胞与颗粒细胞相互突触的特殊性质。
