Immunohistochemical study of proteins linked to apoptosis in rat fetal kidney cells following prepregnancy adriamycin administration in the mother.

Adriamycin is an antibiotic of the anthracycline group. In a previous study, we showed that administration of a single dose of adriamycin (i.p. injection, 5mg/kg body weight) 4 weeks before pregnancy in female Wistar rats induced histological changes in the fetal renal cells typical of apoptosis and also over-expression of heat shock proteins (HSP70). Using a similar experimental model, we have now examined renal cells in fetuses (gestation day 20) to investigate the pathways of the transduction signal of apoptosis in these cells that is induced by prepregnancy maternal administration of adriamycin. Immunolocalization of several proteins - p53, Bax, Apaf-1 and caspase 9 - which take part in the mitochondrial pathway of apoptosis and caspase 12, which takes part in the endoplasmic reticulum pathway of apoptosis, was determined. The results showed that adriamycin administered to the mother rat before pregnancy subsequently induced changes in fetal kidneys involving both the mitochondrial pathway of apoptosis, with increased labeling of the proteins p53, Bax, Apaf-1 and caspase 9, and the endoplasmic reticulum pathway of apoptosis, with increased labeling of caspase 12. Immunolabeling of these proteins was quantified using an image analysis program.