Adriamycin activity's durational governance of different cell death types and zonality in rat liver acinus. Immunohistochemical studies

摘要

The aim of this study was to develop and examine a model of apoptosis and necrosis of hepatocytes induced by a damaging factor - adriamycin, correlating time after its administration with cell death type, and to investigate the localisation within theliver acinus of hepatocytes dying in these two ways. The results obtained in the present and previous studies were compared in order to make a map of cell death localisation in the liver acinus, showing the effect of time in action and dose of adriamycin. The experiment was perfonned on 32 female Wistar rats, divided into four groups: 1 and 11 - experimental, and 111 and IV -control. Adriamycin (3 mg/kg b.w.) was administered intraperitoneally to rats in groups 1 and 11, and the rats were decapitated after four (group I) and eight (group 11) weeks. Animals in control groups 111 and IV were given 0.5 mL of 0.9% NaCl solution, and decapitated atler four and eight weeks respectively. Sections of the hver were examined with a three-stage immunohistochemical method. This method allowed to examine hepatocytes qualitatively and quantitatively for the presence of proteins involved in three types of apoptosis: induced by the mitochondrial pathway (caspase 3, 9), the intrinsic pathway related to endoplasmic reticulum stress (caspase 3, 12), and the extrinsic pathway (caspase 3, 8). One of the inflammatory markers, caspase 1, was also examined. The zonal localisation of all tliree types of apoptosis was assessed in the liver tissue. More oxidated hepatocytes indicated only signs of the internal initochondrial pathway, whereas less oxidated hepatocytes induced the internal reticular pathway and the external apoptotic pathway. The period between adriamycin administration and hepatic cell investigation was a main factor of the process. A longer period post insult resulted in a more pronounced effect of the activation of apoptosis. Sections explored eight weeks after treatment with different doses of the drug (3 and 5 mg/kg in the previous study) showed a similar intensity of apoptosis.