| Research Abstract |
There exist four different kinds of cells in the hepatic sinusoid, i. e. endothelial cells, Kupffer cells, perisinusoidal stellate cells, and the liverassociated Nk cells(pit cells). These cells communicated Intercellularly and also with parenchymal cells by various chemical mediators and cytokines. For the better understanding of their functions, it is necesssary to know the three dimensional structures and Intercellular relationship of the sinusoid. For this purpose the Golgi method is useful for the morphological study of liver sinusoidal cells. The stellate cells display two patterns of cytoplasmic processes, perisinusoidal and Intersinusoidal. The perisinusoidal processes are characteristically studded with thornlike microprojections, whereas the intersinusoidal ones are not. Cytoplasmic processes of the stellate cells developed rapidly during early postnatal stages. In culture system we observed the developing pattern of the cytoplasmic processes of these cells by cinematography. We proved the contraction of these cells by the administration of prostaglandin E2 and the-Kupffer cell-conditioned medium. This phenomenon Is reversible. This- finding Indicates that the function of the stellate cells Is modulated by the Kupffer cells.
We analysed the adhesion of lymphocytes Including pit cells to the endothelial cells In vivo by cinematography. After the i. v. injection of OK-432, adhering lymphocytes Increase In number, but the retention time Is rather short. Kupffer cells play an Important role in an augmentation of cytotoxic activity by pit cells. Kupffer cells and pit cells increase in number during the liver regeneration, however, the functional meaning of this increase is not known.
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