Watanabe Y, Mori K, Imamura K, Takagi S F, Hayaishi O
Brain Res. 1986 Jul 23;378(2):216-22. doi: 10.1016/0006-8993(86)90924-8.
Recent work in our laboratory has demonstrated that prostaglandin (PG) D2 and the enzyme activities for its biosynthesis and inactivation are highly concentrated in the olfactory bulb and that the mitral cell layer of the bulb is enriched with PGD2-binding protein. We therefore investigated the role of PGD2 in the processing of odor signals in the rabbit olfactory bulb by an electrophysiological technique. Iontophoretic (-100 nA, 20 s), intra-arterial (0.0125-0.1 mg/kg) and intravenous (i.v., 0.05-0.3 mg/kg) administration of PGD2 enhanced and prolonged the responses of mitral cells to some of the olfactory stimuli tested. The extent and duration of granule cell inhibition of mitral cells were assessed by recording field potential responses in the bulb to paired lateral olfactory tract volleys. The i.v. administration of indomethacin or diclophenac, both of which are inhibitors of PG biosynthesis, resulted in prolongation of the granule cell inhibition of mitral cells without any significant change of the conditioning amplitudes. It also caused the reduction of the spike responses of mitral cells to olfactory stimuli. After treatment with indomethacin, the i.v. administration of PGD2 (1 mg/kg) rapidly reduced the duration of the granule cell inhibition of mitral cells. These results indicate that PGD2 plays a modulatory role in the mitral cell responses to odor stimuli by suppressing the inhibitory synaptic inputs from granule cells to mitral cells.
我们实验室最近的研究表明，前列腺素（PG）D2及其生物合成和失活的酶活性高度集中在嗅球中，并且嗅球的二尖瓣细胞层富含PGD2结合蛋白。因此，我们通过电生理技术研究了PGD2在兔嗅球气味信号处理中的作用。离子电渗法（-100 nA，20秒）、动脉内注射（0.0125 - 0.1 mg/kg）和静脉注射（i.v.，0.05 - 0.3 mg/kg）PGD2增强并延长了二尖瓣细胞对某些测试嗅觉刺激的反应。通过记录嗅球对成对的外侧嗅束脉冲的场电位反应，评估颗粒细胞对二尖瓣细胞抑制的程度和持续时间。静脉注射吲哚美辛或双氯芬酸，这两种都是PG生物合成的抑制剂，导致颗粒细胞对二尖瓣细胞的抑制延长，而条件刺激幅度没有任何显著变化。它还导致二尖瓣细胞对嗅觉刺激的尖峰反应减少。用吲哚美辛处理后，静脉注射PGD2（1 mg/kg）迅速缩短了颗粒细胞对二尖瓣细胞抑制的持续时间。这些结果表明，PGD2通过抑制颗粒细胞到二尖瓣细胞的抑制性突触输入，在二尖瓣细胞对气味刺激的反应中起调节作用。
