Hayakawa T, Zyo K
Department of Anatomy, Hyogo College of Medicine, Japan.
Anat Embryol (Berl). 1991;184(6):611-22. doi: 10.1007/BF00942583.
We analyzed the termination pattern of axons from the superior central nucleus and the ventral tegmental nucleus of Gudden within the medial mammillary nucleus (MM) in the rat. The neuropil of the MM consists of two classes of terminals, that is, terminals containing round synaptic vesicles and forming asymmetric synaptic contact, and terminals containing pleomorphic synaptic vesicles and forming symmetric synaptic contact. The number of axodendritic terminals with round vesicles is almost equal to that of terminals with pleomorphic vesicles. Almost all axosomatic terminals contain pleomorphic vesicles with symmetric synaptic contact. Injection of WGA-HRP into the central part of the superior central nucleus permitted ultrastructural recognition of many anterogradely labeled terminals within the median region of MM. The labeled terminals contacted mainly intermediate (1-2 microns diameter) and proximal dendrites (more than 2 microns diameter) as well as the neuronal somata. Serial ultrathin sections of neurons of the median region of the MM revealed that 37% of the axosomatic terminals were labeled anterogradely. The pars compacta of the superior central nucleus had reciprocal connections with the median region of MM. The axon terminals from this nucleus occupied 53% of axosomatic terminals, and contacted mainly intermediate dendrites. Following injection of WGA-HRP into the ventral tegmental nucleus, many labeled terminals were found in the medial and lateral regions of MM. They contacted mainly intermediate dendrites as well as neuronal somata. In the medial region, 78% of axosomatic terminals contacting retrogradely labeled neurons were labeled anterogradely. All labeled terminals from these nuclei contained pleomorphic vesicles, and made symmetric synaptic contact.
我们分析了大鼠内侧乳头体核（MM）内来自上中央核和古登腹侧被盖核的轴突终末模式。MM的神经毡由两类终末组成，即含有圆形突触小泡并形成不对称突触接触的终末，以及含有多形性突触小泡并形成对称突触接触的终末。含圆形小泡的轴-树突终末数量几乎与含多形性小泡的终末数量相等。几乎所有的轴-体终末都含有多形性小泡并形成对称突触接触。将WGA-HRP注入上中央核中部后，可在超微结构水平识别MM中间区域许多顺行标记的终末。这些标记终末主要与中间（直径1-2微米）和近端树突（直径超过2微米）以及神经元胞体接触。MM中间区域神经元的连续超薄切片显示，37%的轴-体终末为顺行标记。上中央核的致密部与MM中间区域有相互连接。来自该核的轴突终末占轴-体终末的53%，主要与中间树突接触。将WGA-HRP注入腹侧被盖核后，在MM的内侧和外侧区域发现许多标记终末。它们主要与中间树突以及神经元胞体接触。在内侧区域，与逆行标记神经元接触的轴-体终末中，78%为顺行标记。来自这些核的所有标记终末都含有多形性小泡，并形成对称突触接触。
