大鼠终纹床核卵圆核的传入联系——FG和WGA-HRP逆行追踪法研究

CONNECTIONS OF THE OVAL NUCLEUS AND ITS ADJACENT AREAS OF THE BED NUCLEI OF THE STRIA TERMINALIS IN THE RAT. AFFERENT CONNECTIONS——A FLUOROGOLD AND WGA-HRP RETROGRADE TRACT-TRACING STUDY

实验选用雄性Sprague-Dawley大鼠24只,分2组进行。第1组11只,将2～4％的荧光金(fluoro-gold,FG)水溶液加压或电泳导入一侧终纹床核群卵圆核,检查中枢不同区域逆行标记细胞的分布。第2组13只,将WGA-HRP/HRP混合水溶液注入一侧卵圆核,检查逆行标记细胞在不同脑区的分布。比较两组结果,发现所标记的神经元分布范围和趋势大致相同;但FG标记的神经元突起远较HRP标记长,并在对侧某些区域出现标记细胞。这表明作为一种逆行束路示踪剂,FG较WGA-HRP敏感性高。逆行标记细胞主要见于梨状皮质、纹底、海马下托、视前区、斜角带水平支、大细胞视前区、腹侧苍白球;杏仁体的中央核、内侧核、皮质核;丘脑的中线核群、束旁核、室旁核有散在的标记细胞;下丘脑的前区、外侧区、背侧区和腹内核、弓状核、前乳头体核有数量不等的标记细胞;中脑的中央灰质腹侧半、中缝背核、脚桥被盖核、中缝核群和腹侧被盖区、黑质致密带、脚间核、束间核;脑桥的臂旁核、蓝斑、三叉神经中脑核、A_5区、中缝核群;延髓的孤束核/迷走神经背核和C_1/A_1等区域均可看到一定数量的标记细胞。本工作首次较系统地观察了大鼠卵圓核的传入纤维联系。

The present experiments were designed to study the afferent connections of the oval nucleus (Ov) of the bed nuclei of the stria terminalis (BST) using fluoro-gold (FG) and WGA-HRP as retrograde tracers. After injection of FG or WGA-HRP into the Ov area of the male SpragueDawley rats, a number of retrogradely labeled neurons were observed in the piriform cortex, fundus striati, subiculum, preoptie areas, horizontal limb of the diagonal band, ventral pallidum, magnocellular preoptic area, central (Ce), medial and cortical nuclei of the amygdala. A few neurons in the midline nuclei of the thalamus. were labeled. Many labeled neurons were found in the anterior, dorsal and lateral hypothalamic areas, ventral medial, arcuate and premammillary nuclei of the hypo thalamus. In the brainstem many labeled neurons were seen in the ventral part of the midbrain central gray, dorsal raphe nucleus, pedunculopontine tegmental nucleus, ventral tegmental area, compact zone of the substantia nigra, interpeduncular nuclei, interfascicular nucleus, raphe nuclei, parabrachial nuclei, locus coeruleus, mesencephalie trigeminal nucleus, dorsal vagal complex, A_5 and A_1 cell groups.In general, the distribution patterns of the labeled neurons of both tracers were quite similar except that FG labeled neurons showed much longer processes than WGA-HRP's, and some FG labeled neurons were also found in a few contralateral structures, such as central and medial nuclei of the amygdala and the horizontal limb of the diagonal band, where no WGA-HRP labeled neurons were observed.The results of this retrograde tract-tracing study together with our previous. anterograde tract-tracing study indicate that there are reciprocal connections between the Ov and the Ce, posterior part of the lateral hypothalamus and several brainstem structures.