A. Kohler et al., DETECTION OF P-GLYCOPROTEIN MEDIATED MDR MXR IN CARCINUS-MAENAS HEPATOPANCREAS BY IMMUNO-GOLD-SILVER LABELING/, Marine environmental research, 46(1-5), 1998, pp. 411-414
Carcinus maenas were sampled in the German Bight for immunohistochemis
try, histology and parallel chemical analysis of organochlorines. Incu
bations were performed with a monoclonal antibody against P-glycoprote
in which mediates multixenobiotic resistance in order to develop MXR i
n hepatopancreas. The data showed that MXR was highly, expressed at th
e microvilli of epithelial cells while inside epithelial cells of the
tubules MXR was restricted to a specific cell type, the transitional s
tage between fibrillar (F) cells and blister (B) cells. These cells we
re rich in lysosomes as was demonstrated by high acid phosphatase acti
vity. In aging B cells, fusion events of the lysosomal compartment to
one large vacuole were observed to he accompanied by a loss of MXR pro
tein content. Subsequently, B cells were eliminated from the epitheliu
m into the lumina where the cell debris was incorporated into the faec
es. It is concluded that F/B cells appear to be specialized for accumu
lation of toxic compounds and their digestion and elimination. (C) 199
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