Immunogold electron microscopy showing the localization of CGB and SgII in secretory granule-like vesicles (large dense-core vesicles) in astrocytes of brain tissues.

Astrocytes from human brain tissues were immunolabeled for CGB (A) and SgII (B) (15 nm gold) with the affinity purified CGB and SgII antibodies, respectively. The CGB- or SgII-labeling gold particles (indicated by arrows) were primarily localized in the secretory granule-like vesicles (SG) with some in the endoplasmic reticulum (er), but not in the mitochondria (M). In the control experiments without the primary antibodies no gold particles were seen in the secretory granule-like vesicles (not shown). Bar = 200 nm.