枕下区肌硬膜桥普遍性存在及其结构特征的比较解剖学研究

The “myodural bridge” is fibrous connective tissues between the muscles, ligaments and the spinal dural mater in the sub-occipital region. Its functional significance is a hot research in the field of anatomy all the time. According to the previous studies, there was a new hypothesis in our research group that the cerebrospinal fluid circulation would be affected by head movement. This effect is achieved by the “myodural bridge” though pulling the spinal dural mater. This hypothesis was validated by the cerebrospinal fluid circulation experiment further. Therefor whether the “myodural bridge” is a normal universal structure also exist in other mammals, and how the “myodural bridge” influence cerebrospinal fluid circulation. These questions seem more important for the “myodural bridge” participating in the dynamic mechanism of cerebrospinal fluid circulation. So in this study, P45 plastination technique, special staining, immunofluorescence, 3D reconstruction technique will be used to confirm whether the “myodural bridge” is also exist in other mammals. The properties of fibers, vascular distribution and morphology of nerve endings of the “myodural bridge” will also be studied. The results will be compared with that of the “myodural bridge” in human beings. The function of this structure will be analyzed by comparing the difference of this structure in different mammals. The existence of the “myodural bridge” will confirmed in other mammals in this study and structure characteristics of the “myodural bridge” will be refined. The results of this study will be the comparative anatomical evidence for the study of the “myodural bridge” participating in dynamic mechanism of cerebrospinal fluid circulation.

肌硬膜桥是枕下区肌肉及韧带与硬脊膜之间的纤维连接结构，其存在的功能意义一直是解剖学界研究的热点。据以往研究结果，本课题组对肌硬膜桥的功能提出了新的假说，即头部运动时，枕下区肌硬膜桥会通过对硬脊膜的牵拉，影响局部脑脊液循环，参与脑脊液的循环动力机制。并进一步在脑脊液循环动力实验中初步证明了此假说。因此枕下区肌硬膜桥是否普遍存在于其它哺乳动物，以及如何参与脑脊液循环，对揭示其参与脑脊液循环的动力机制就显得尤为重要。本课题拟采用P45断层塑化、特殊染色、免疫荧光标记、三维重建等技术，首次在人体之外的其它哺乳动物体内研究枕下区肌硬膜桥，探究肌硬膜桥在其它哺乳动物体内的存在情况，纤维性质，血管分布情况及神经末梢形态，并与人类肌硬膜桥相比较。通过结构比较分析结构功能，从形态学上明确肌硬膜桥在哺乳动物中的普遍存在，并揭示其结构特征，为肌硬膜桥参与脑脊液循环的动力机制研究提供比较解剖学证据。

肌硬膜桥是枕下区肌肉及韧带与硬脊膜之间的纤维连接结构。据以往研究结果，本课题组提出了肌硬膜桥参与脑脊液的循环动力机制的假说。枕下区肌硬膜桥是否普遍存在于其它哺乳动物，以及如何参与脑脊液循环，对揭示其参与脑脊液循环的动力机制尤为重要。本课题采用P45断层塑化、大体解剖、组织学染色、扫描电镜技术，首次在人体之外的其它哺乳动物体内研究肌硬膜桥，并比较其结构的差异。. 大体解剖,P45塑化切片及组织学HE染色结果显示除江豚外，各纲目动物枕后区肌肉构成与人类枕下区肌肉构成相似。于寰枕间隙，各纲目动物的头背侧小直肌与寰枕后膜，寰枕后膜与硬脊膜之间均存在纤维结缔组织连接。与人类寰枕间隙肌硬膜桥的存在形式相似。江豚由于前三个颈椎的融合，不存在头前、后斜肌。枕后区仅存在直肌。寰枕间隙无膜状结构覆盖，头背侧直肌直接穿入寰枕间隙，连接于硬脊膜。. 肌硬膜桥在各纲目哺乳动物体内普遍存在，但也存在结构差异。包括构成寰枕间隙骨性结构形态差异，寰枕间隙大小差异，骨性结构的位置关系差异，肌硬膜桥纤维来源差异等。. 组织学特殊染色确定了肌硬膜桥为I型胶原纤维，具有较强的抗拉伸性和延展性，能够有效传递枕下肌收缩传递的拉力。肌硬膜桥纤维之间存在大量的静脉窦。肌硬膜桥通过肌肉收缩所带来的对于其纤维内部的静脉窦内血液的挤压作用，间接保证了脑脊液的正常循环。. 本课题探究了肌硬膜桥在哺乳动物体内的存在情况及结构差异，并与人肌硬膜桥相比较。通过结构比较分析结构功能，从形态学上明确了肌硬膜桥在哺乳动物中的普遍存在，并揭示其结构特征，为肌硬膜桥参与脑脊液循环的动力机制研究提供比较解剖学证据。