Enhanced ultrastructural preservation of cartilage proteoglycans in the extended state.

Abstract

We investigated the preservation of proteoglycan (PG) structure in rat epiphyseal cartilage using N-N-dimethylformamide (DMF) dehydration before embedding. After aldehyde fixation, specimens with and without routine osmium post-fixation were dehydrated in graded DMF and embedded in either Spurr's resin or Lowicryl K4M resin. Standard ethanol dehydration with Spurr or Lowicryl embedding techniques resulted in the formation of condensed PGs, called matrix granules. DMF dehydration before embedding greatly improved the preservation of PG structure and resulted in an extended appearance of PGs closely resembling the fine filamentous network of cartilage tissues processed by rapid freezing and freeze-substitution. However, en bloc staining of aldehyde-fixed specimens with cationic reagents before or during DMF dehydration induced the condensation of PGs and resulted in the formation of matrix granules. These observations demonstrate that DMF, a mild dehydration agent, dramatically improves PG preservation without a harmful effect on aldehyde-fixed PG structure and can be utilized regardless of routine post-fixation.

• Authors: A Kagami, M Takagi, M Hirama, Y Sagami, T Shimada
• Journal: The journal of histochemistry and cytochemistry : official journal of the Histochemistry Society (J Histochem Cytochem) Vol. 38 Issue 6 Pg. 901-6 (Jun 1990) ISSN: 0022-1554 [Print] United States
• PMID: 2335743 (Publication Type: Journal Article)

Chemical References

• Proteoglycans
• Dimethylformamide

Topics

• Animals
• Dimethylformamide
• Growth Plate (ultrastructure)
• Male
• Preservation, Biological (methods)
• Protein Conformation
• Proteoglycans (ultrastructure)
• Rats
• Rats, Inbred Strains