Research Product

Mammalian P-glycoprotein is a highly conserved 170-kD integral plasma membrane protein functioning as an energy dependent efflux pump of exogenous and endogenous lipophilic aromatic compounds entering the cell by diffusion. In this study, the tissue specificity of one polyclonal (pAb) and three monoclonal (mAbs) antibodies to mammalian P-glycoprotein were identified in paraffin-embedded, parasagittal whole body sections of the guppy, Poecilia reticulata. Pab mdr (Ab-1) and mAbs C219, C494 and JSB-1 demonstrated differential staining patterns in the following tissues: bile canaliculi in the liver, exocrine pancreas, lumenal surface of the intestinal epithelium, renal tubules, interrenal tissue, branchial blood vessels, gas gland, pseudobranch, and the gill transverse septa. Positive P-glycoprotein expression in P. reticulata correlates well with published results for homogogous mammalian tissues of secretory and execretory function. These data indicate that one or more highly conserved members of the P-glycoprotein transporter family exist in a teleost species which can be detected using commercially available mammalian antibodies.