It has been known that glomerular capillary loop s of living mouse kidney s are perpetually stretched by hydraulic pressures in blood capillaries , whereas those in excised kidneys receive no such stretching forces. Filtration slits between foot process es of podocytes were reported to be widely open to facilitate passage of the glomerular filtrate in vivo [3]. It has also been reported that the foot processes are rich in contractile proteins, such as actin, myosin, and α-actinin, and capable of such actin-mediated movement [11]. Through this active movement, the podocytes may regulate the glomerular filtration rate , thereby influencing hydraulic pressures across the glomerular basement membrane , as reported before [3]. Therefore, the blood pressures must be steadily maintained at the time of exposure to quick freezing with IVCT, and the dynamically changing filtration slit s are found to be wider under normal blood circulation than the heart-arrestcondition . The glomerular hydraulic pressure s might be partially regulated by the relative width of the filtration slits. Therefore, the total width of the filtration slits plays an important role in providing a porous theory that controls hydraulic conductivity and water flow [3, 12].