Research On Improvement Of Ccerebral Perfusion Fixation And Tissue Optical Clearing Technique

Tissue optical clearing technique is a hotspot in biomedical research in recent years.Biomedical samples can be transparent after being processed by tissue optical clearing technique so that researchers can observe the three-dimensional structure of tissue samples through existing imaging techniques.The currently reported transparent techniques have their own advantages and disadvantages in terms of operational complexity,fluorescence compatibility,and tissue deformation.It is necessary to develop new transparent techniques.In long-term experiments,we find that the adequacy of tissue perfusion fixation is very important in tissue transparency,and whether the perfuision is sufficient directly affects the transparency of the tissue.This paper firstly reviews the techniques of-tissue fixation and optical clearing,then the experiments was carried out,the specific content and results are as follows:(1)Improved perfusion fixation of brain tissue.The experimental group was perfused via bilateral common carotids and the control group was perfused by transcardiac perfusion.Brains were removed for transparency and pathological analysis.The results show that saline and fixative are saved by more than half in the experimental group,the transmittance of brain tissue sections was better and the statistical analysis was significantly different in the near-infrared band(P<0.05).At the same time,compared with the control group*,HE staining and immunofluorescence were also better,the number of red blood cells was significantly reduced(P<0.05).(2)New tissue transparent solution research.After consulting a large amount of literature,a hydrophilic transparent solution was developed which was used to clear brains and livers.At the same time,the other brain was stained by Sudan ?,and the other liver was stained by picrosirius red.Finally,the transparent tissue was sectioned and stained to observe the changes of cells.The results show that the mouse brain and the rabbit olfactory bulb became more transparent in about 2 weeks.The nerve orientation of white matter fibers can be seen in the mouse brain stained by Sudan ? and the vascular network was well recognized inside the liver stained by picrosirius red.Nissl staining and luxol fast blue staining showed that the nucleus of the brain was intact,the cytoplasm was unclear,and the gap between cells became larger.We conclude that bilateral common carotid perfusion technique can improve the transmittance of transparent brains and has certain application value in the study of transparent brain.The developed transparent technology can be better clear thinner tissue and achieve overall dyeing of the tissue,which may provide a new breakthrough for the development of tissue optical clearing and dyeing technology.