Calcium localized in juxtanuclear granules of epiphyseal chondrocytes with a dilute glyoxal bis(2-hydroxyanil) solution.

The glyoxal bis(2-hydroxyanil) (GBHA) method for staining labile calcium deposits in chondrocytes was modified. Fresh blocks of epiphyseal cartilage stained in this dilute GBHA solution revealed calcium in the juxtanuclear Golgi vesicles, each approximately 1 mu in diameter. Prolonged staining revealed previously described 0.5 mu granules throughout the cytoplasm which tended to mask the juxtanuclear reaction. The red GBHA reaction product was believed to be a chelate of calcium since it was removable with EGTA, and stable in Na2CO3 and KCN solution. When the tissue blocks stained with the dilute GBHA solution were restained with the original concentrated GBHA solution, refractile bodies containing red GBHA-positive granules were revealed at the periphery of the hypertrophied chondrocytes. The presence of calcium in the juxtanuclear Golgi vesicles and in the pericellular refractile bodies may indicate that the Golgi is involved in the transport of minerals to the matrix.