Hyperglycogenic secondary center cells in rat femurs

Abstract

The cells forming the secondary center have been described and compared to the hypertrophic chondrocytes of the primary growth plate (ref.I,2). In an attempt to clarify the nature of the vacuolization and associated cell hypertrophy reported to also take place within the chondrocytes of the secondary center prior to the onset of ossification an attempt to improve chondrocyte morphology was made. Glutaraldehyde fixation followed by buffered osmium was compared to tissue fixed with potassium ferrocyanide reduced osmium.Cartilage slices from 5-7 day rats (distal femur) were fixed in 2% glutaraldehyde/0.1M Na phosphate pH 7.4 (2 hrs.); rinsed in 0.1M N phosphate buffer plus 0.1M sucrose (15. min.); post fixed in 1.5% potassium ferrocyanide in aqueous OSO4 or in 2% OSO4/0.1M Na phosphate (2 hrs.); rinsed in 0.1M Na acetate (pH 6.3); en bloc stained in .25% uranyl acetate/0.1M Na acetate; dehydrated in alcohol and Spurr embedded.