Cell surface heparan sulfate proteoglycan and chondroitin sulfate proteoglycan of arterial smooth muscle cells.
Cell surface proteoglycans of aortic smooth muscle cells of atherosclerosis-susceptible White Carneau (WC) and atherosclerosis-resistant Show Racer (SR) pigeons were compared to determine differences that may be involved in the greater proliferative properties of cultured WC cells. Using [35S]-sodium sulfate and [3H]-glucosamine as labeling precursors, chondroitin sulfate-proteoglycan (CS-PG) and heparin sulfate-proteoglycan (HS-PG) were identified as distinct molecules associated with the plasma membrane. Heparan sulfate-proteoglycan was reduced up to 50% in WC compared with SR cells, and, based on interaction with ion-exchange resin, had a lower charge density. These differences were not observed for the CS-PG from the two cell types. The mode of association of the cell surface PG with the plasma membrane was examined. Dissociation with 1 mol/l (molar) sodium chloride indicated that less than 10% of total cell surface PG were ironically associated with the cells. The remainder required detergent extraction, suggesting hydrophobic interactions with the plasma membrane. Both CS-PG and HS-PG displayed affinity for octyl sepharose and both were identified in isolated plasma membranes. These data present the first description of a hydrophobic CS-PG that is a significant and distinct cell-associated PG in arterial smooth muscle cells. The observation of decreased and structurally altered HS-PG in WC compared with SR cells is consistent with a potential growth regulatory function for this molecule.
Edwards
I J
IJ
Department of Comparative Medicine, Bowman Gray School of Medicine of Wake Forest University, Winston-Salem, North Carolina 27157-1040.
Wagner
W D
WD
D000818:Animals; D001011:Aorta / Q000737:chemistry* / Q000166:cytology*; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism / Q000648:ultrastructure; D002478:Cells, Cultured; D002809:Chondroitin Sulfates / Q000032:analysis* / Q000378:metabolism; D002852:Chromatography, Ion Exchange; D010856:Columbidae; D005944:Glucosamine / Q000378:metabolism; D006497:Heparan Sulfate / Q000032:analysis* / Q000378:metabolism; D009131:Muscle, Smooth, Vascular / Q000737:chemistry* / Q000166:cytology* / Q000648:ultrastructure; D012979:Sodium Radioisotopes; D013431:Sulfates / Q000378:metabolism; D014316:Tritium
D002809:Chondroitin Sulfates; D005944:Glucosamine; D006497:Heparan Sulfate; D012979:Sodium Radioisotopes; D013431:Sulfates; D014316:Tritium; C012036:sodium sulfate