大鼠嗅结节与丘脑的双向纤维联系—HRP法研究

DUAL CONNECTIONS BETWEEN THE OLFACTORY TUBERCLE AND THE THALAMUS IN THE RAT—HRP METHOD STUDY

应用HRP顺、逆轴突传递法研究了29例大鼠嗅结节(OT)与丘脑的纤维联系,结果如下:将HRP注入一侧嗅结节,逆行标记细胞规律性地出现在丘脑同侧室旁核(Pv),带旁核(Pt)和束旁核(Pf)。大多数例中还出现在同侧背内侧核(Tm)、后正中核(PoMn)和束旁下核(Spf)。上述各核按标记细胞的多少排列依次为:Pf、Tm、Pv、Pt、PoMn和Spf。顺行标记终末在Tm中央部和外侧缰核(Lh)中较密集,在Fv、Pt、Pf、PoMn和Spf中较稀疏。实验证明,凡发纤维至OT的丘脑核团,同时也接受OT的纤维,它们之间存在着往返纤维联系。大鼠PoMr和Spf与OT的纤维联系为本文首次报告,前人关于丘脑与嗅结节联系的分歧意见在本实验中得到了澄清;本文最后对嗅结节与丘脑联系的机能意义进行了简要讨论。

The dual connections between the olfactory tubercle (OT) and the thalamus were studied with the method of anterograde and retrograde axonal transport of HRP in 29 rats. The results were as follows: with injecting HRP into unilateral OT, retrogradely labeled neurons were found in the ipsilateral paraventricular nucleus (Pv), parataenial nucleus(Pt), parafascicular nucleus(Pf) regularly and in the dorsomedial nucleus(Tm), posterior median nucleus(PoMn), and subparafascicular nucleus (Spf)in most cases. According to the amount of labeled cells, the above mentioned thalamic nuclei would appear in this order: Pf, Tm, Pv, Pt, PoMn and Spf. Anterogradely labeled terminals were found dense in the lateral habenula and the centralsegment of Tin, sparse in the Pv, Pf, Pt, PoMn and Spf. These results suggest that the thalamic nuclei projecting to OT receive inputs from OT simultaneously, dual connections exist between OT and these thalamic nuclei. Connections between OT and PoMn, Spf were reported here for the first time in the rat. The discrepancy on the connections between OT and the other thalamic nuclei was clarified in this study. The functional aspects in relation to these connections were discussed briefly,