Further characterization of the human adrenal-derived P-glycoprotein recognized by monoclonal antibody MRK 16 reacting with only human P-glycoprotein.
This paper describes further characterization of the 170-180-kDa glycoprotein (P-glycoprotein) recognized by the monoclonal antibody MRK 16 in the human adrenal. By electron microscopy, P-glycoprotein was observed in the adrenal cell membranes. However, MRK 16-defined P-glycoprotein was not found in cow, pig, horse, monkey or rabbit adrenal, indicating that MRK 16 recognizes the non-homologous part of P-glycoprotein of various species. Eleven out of 16 adrenal tumors including 4 cases of primary aldosteronism and 7 cases of Cushing syndrome were intensely stained with MRK 16, whereas pheochromocytoma, non-functioning adrenocortical adenoma with no associated increase of serum adrenal-derived hormones and myolipoma of the adrenal were not. Finally, P-glycoprotein-MRK 16-protein A-Sepharose complex derived from human adrenal possessed marked ATPase activity. Taken together, these data suggest that P-glycoprotein may play a physiological role in the human adrenal.
Sugawara
I
I
Department of Pathology, University of Tokyo.
Hamada
H
H
Nakahama
M
M
Okamoto
S
S
Tsuruo
T
T
Mori
S
S
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000251:Adenosine Triphosphatases / Q000378:metabolism; D000310:Adrenal Gland Neoplasms / Q000032:analysis; D000311:Adrenal Glands / Q000032:analysis*; D000911:Antibodies, Monoclonal; D002460:Cell Line; D004317:Doxorubicin; D004351:Drug Resistance; D006801:Humans; D008562:Membrane Glycoproteins / Q000032:analysis* / Q000276:immunology / Q000378:metabolism; D008854:Microscopy, Electron; D013045:Species Specificity
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000911:Antibodies, Monoclonal; D008562:Membrane Glycoproteins; D004317:Doxorubicin; D000251:Adenosine Triphosphatases