Presence of laminin B chain-like protein in bovine and rat adrenal chromaffin granules.
The presence of a glycoprotein laminin in bovine adrenal chromaffin granules was examined by SDS-PAGE followed by immunoblotting. The two chromaffin granule membrane fractions were obtained by linear sucrose gradient centrifugation followed by freezing and thawing and gel-filtration of the chromaffin granule-rich fraction, respectively. The purity of the granules in these fractions was examined by electron microscopy. These fractions contained laminin B chain-like immunoreactivity as a major immunoreactive component against anti-laminin. Laminin A chain-like immunoreactive protein was undetectable. The soluble fraction of the chromaffin granules contained no immunoreactive peptide. The presence of laminin-like immunoreactivity in the chromaffin granules was confirmed by immunocytochemical study. Laminin B chain-like immunoreactivity was also identified in the rat adrenal chromaffin granule fraction. Laminin A chain was hardly detected, as in the case of bovine adrenals. Structure of laminin in chromaffin granules in bovine and rat adrenals may be different from that of mouse Englebrethe-Holm-Swarm sarcoma laminin. The functional significance of laminin B chain-like protein in the granules is unknown at present.
Fujino
Y
Y
Department of Pharmacology, Teikyo University School of Medicine, Tokyo.
Fujii
T
T
Daimon
T
T
D000313:Adrenal Medulla / Q000378:metabolism; D000818:Animals; D002417:Cattle; D002458:Cell Fractionation; D002837:Chromaffin Granules / Q000737:chemistry* / Q000648:ultrastructure; D004591:Electrophoresis, Polyacrylamide Gel; D005629:Frozen Sections; D015151:Immunoblotting; D007797:Laminin / Q000032:analysis* / Q000737:chemistry; D008297:Male; D051379:Mice; D008854:Microscopy, Electron; D016253:Microscopy, Immunoelectron; D051381:Rats; D017208:Rats, Wistar; D012513:Sarcoma, Experimental / Q000737:chemistry
D007797:Laminin