Effects of Cortisone on Regenerating Rat Liver* by Stanley L. Einhorn,~ Erich Hirschberg, and Alfred Gellhorn
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چکیده
Many laboratory and clinical findings point to a definite inhibitory effect of cortisone on total body and organ growth (1-18). The central importance of the synthesis of nucleic acids in growth processes and in the general economy of the cell requires no elaboration. The effect of various growth inhibitors on nucleic acid metabolism has engaged the attention of a number of investigators (19-25); the studies of Skipper et al. (20), Lowe and collaborators (25), and Cavallero and associates (26) provide the background of the present investigation. The effectiveness of cortisone, as of other growth-inhibiting agents, appears to be correlated with the rate of growth of the target tissue; in general, the most rapidly growing tissues, whether embryonic, neoplastic, or lymphoid, are affected most markedly. Regenerating rat liver was selected for the present study for a variety of reasons. The size and accessibility of the organ, the relative uniformity of its cell population, the fairly reproducible nature of the restorative process after partial hepatectomy, and the extensive literature available on different aspects of this biological system (27-41) may be cited. An evaluation of the advantages and disadvantages of regenerating rat liver for studies of this type has been made in a previous publication from this laboratory (19). In the present investigation, the effect of cortisone on the rate of liver regeneration and on nucleic acid metabolism during the restorative process was examined from various points of view. In a paper which became available to us during the preparation of this manuscript, Roberts et al. (42) summarized their results on the effect of large doses of cortisone on the regeneration of mouse liver after partial hepatectomy. Their results are in substantial agreement with our findings in the rat.
منابع مشابه
Effects of Cortisone on Regenerating Rat Liver
The effects of continuous administration of cortisone on the metabolism of regenerating rat liver have been studied. Whereas the restoration of the weight of the liver after partial hepatectomy was not markedly affected by cortisone, the multiplication of cells was reduced to a significant degree after the first 2 days of regeneration. Liver restoration in terms of nucleic acids was similarly i...
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تاریخ انتشار 2003