STUDIES ON THE STEREOTAXIC APPARATUS AND BRAIN ATLAS OF THE HOUSE MUSK SHREW

家麝鼠（Suncus murinus）被S.Oda和k.o kondo驯化为新的实验动物，并命名为“Suncus”。研究表明，子穴在中枢神经系统和内分泌控制系统中具有多种独特的特征。本课题的目的是设计一种适用于太阳的立体定向装置，并确定太阳脑的立体定向坐标。小鼠类的体大小与幼鼠或小鼠相似，但小鼠类的立体定位器不能用于小鼠类，因为小鼠类的头部区域的解剖特征与啮齿动物非常不同：(1)鼓室和外耳道不是骨的，而是膜状的，部分是软骨的。(2)耳廓外孔远向腹侧移位。两侧毛孔之间的轴穿过喉部。本研究设计的适用于鼠类的耳栅比用于啮齿动物的耳栅更粗、更短；根尖直径3mm，基部直径5mm，长度5mm，基部附着直径10mm的树脂垫。这些耳条可以牢固地固定太阳穴的头部，并且不会从侧面对喉部施加压力。黑子颅骨颞面在口-口轴上呈直线而非圆形。当颞面通过齿杆调节保持水平时，大脑颞面也保持水平。在上述情况下，通过耳杆0平面的垂直横向轮廓包括脑纵裂尾端和乳状体尾极。本研究将此平面作为立体滑行坐标的横向0平面。与颞面平行并穿过耳条或齿条的平面不能用于水平标准平面。因为它们离大脑太靠腹了。本研究采用脑表面作为水平0面。

The house musk shrew ( Suncus murinus ) has been domesticated by S.Oda and K.Kondo as new laboratory animal, and was named "suncus". It has been revealed that the suncus has various unique characteristics in the central nervous system and endocrinological control systems.The purposes of this project are to contrive a stereotaxic apparatus applicable to the suncus and to decide the stereotaxis coordinate of the suncus brain.Body size of the suncus is similar to those of young rats or mice, but stereotaxic apparatus for small rodents can not be used for suncus, because the suncus has very different anatomical features of head region from rodents:(1) tympanic bulla and external acustic meatus are not bony but membranous or, a part, cartilageous. (2)external acustic pore of the suncus shifts far ventrally. and axis between the pores of both side runs through larynx. Ear-bars contrived to be applicable to the suncus in this study are more thick and short than those used for rodents; apical diameter is 3mm. basal diameter is 5mm and length is 5mm, and resin pad of 10mm diameter is attached to basal part. These ear-bars can fix tightly head of the suncus, and do not put pressure upon larynx from lateral sides.Temporal plane of skull of the suncus is not round but straight on oral-aboral axis. When this temporal plane is kept horizontally by adjustment of teeth-bar, cerebral temporal surface is also kept horizontal. Under above mentioned condition, the vertical transverse profile through ear-bar 0 plane contains caudal end of the longitudinal cerebral fissure and caudal pole of the mamillary body. This plane is used as the transverse 0 plane of stereo- taxic coordinate in this study. Planes which are parallel to the temporal plane and run through ear-bars or teeth-bar can not be used for horizontal standard plane. because those are too ventrally shifted from the brain. Brain surface is used as horizontal 0 plane in this study.