目的　观察 α-氨基丁酸 B受体 (GABABR)在大鼠中枢内源性镇痛系统内的定位分布 .方法　 GABABR特异性抗体的免疫组织化学染色方法 .结果　 GABABR样阳性胞体较密集地分布于中缝核簇的核团 ,如中缝背核、中缝正中核、中缝桥核、中缝大核、中缝苍白核、中缝隐核 .此外 ,中脑导水管周围灰质和巨细胞网状核α部内也有 GABABR样阳性胞体 .上述核团内亦可见 GABABR样阳性纤维和终末 .结论　中枢内源性镇痛系统内有 GABABR样阳性胞体、纤维及终末 ,这些阳性结构可能与对该系统的调控有关 Objective To observe the localization of α-aminobutyric acid B receptor (GABABR) in the central nervous system of rats after endogenous analgesia.Methods GABABR-specific antibodies were immunohistochemically stained.Results GABABR-like positive somatic cells were densely distributed in The nuclei of the nucleus raphe, such as the dorsal raphe nucleus, middle meridian nucleus, middle mezzanine nucleus, meso-meridian nucleus, meso-nucleus mesencephalic nucleus and meso-stapelia .In addition, GABABR Like positive soma.GABABR-like positive fibers and terminals were also observed in the above nuclei.ConclusionGCA-positive cell bodies, fibers and terminals in the central endogenous analgesic system may be related to the regulation of this system